diff --git a/config/webpack.config-dev.js b/config/webpack.config-dev.js
index 76461728e..4a0dd6661 100644
--- a/config/webpack.config-dev.js
+++ b/config/webpack.config-dev.js
@@ -28,8 +28,8 @@ export default {
   // switch the source map generation when debugging
   // note, we used 'eval-source-map' before, but since webpack 5.100, it breaks the build
   // (causes 'SyntaxError: redeclaration of function normalize')
-  devtool: 'inline-source-map',
-  //devtool: false, // turn it off completely
+  // devtool: 'inline-source-map',
+  devtool: false, // turn it off completely
 
   entry: path.join(__dirname, '..', 'src/client.js'),
   output: {
diff --git a/src/components/Solutions/SolutionFiles/SolutionFiles.js b/src/components/Solutions/SolutionFiles/SolutionFiles.js
index 13542e7eb..01cba57e4 100644
--- a/src/components/Solutions/SolutionFiles/SolutionFiles.js
+++ b/src/components/Solutions/SolutionFiles/SolutionFiles.js
@@ -145,7 +145,7 @@ const SolutionFiles = ({
                               <OverlayTrigger
                                 placement="bottom"
                                 overlay={
-                                  <Tooltip id={`openfile-${file.id}`}>
+                                  <Tooltip id={`open-file-${file.id}`}>
                                     <FormattedMessage
                                       id="app.solutionFiles.openButton"
                                       defaultMessage="Open preview in dialog"
diff --git a/src/components/Solutions/SourceCodeBox/SourceCodeBox.js b/src/components/Solutions/SourceCodeBox/SourceCodeBox.js
index 56454de06..4fa248331 100644
--- a/src/components/Solutions/SourceCodeBox/SourceCodeBox.js
+++ b/src/components/Solutions/SourceCodeBox/SourceCodeBox.js
@@ -6,12 +6,12 @@ import ReactDiffViewer, { DiffMethod } from 'react-diff-viewer';
 import Prism from 'prismjs';
 
 import Box from '../../widgets/Box';
-import SourceCodeViewer from '../../helpers/SourceCodeViewer';
+import SourceCodeViewer, { SourceCodeHighlightingSelector } from '../../helpers/SourceCodeViewer';
 import ResourceRenderer from '../../helpers/ResourceRenderer';
 import Icon, { CopyIcon, CopySuccessIcon, CodeCompareIcon, DownloadIcon, LoadingIcon, WarningIcon } from '../../icons';
 
 import { getPrismModeFromExtension } from '../../helpers/syntaxHighlighting.js';
-import { getFileExtensionLC, simpleScalarMemoize } from '../../../helpers/common.js';
+import { getFileExtensionLC, simpleScalarMemoize, EMPTY_OBJ } from '../../../helpers/common.js';
 
 const normalizeLineEndings = simpleScalarMemoize(content => content.replaceAll('\r', ''));
 
@@ -45,10 +45,15 @@ const SourceCodeBox = ({
   reviewClosed = false,
   collapsable = false,
   isOpen = true,
+  highlightOverrides = EMPTY_OBJ,
+  setHighlightOverride = null,
 }) => {
   const res = fileContentsSelector(parentId, entryName);
   const [clipboardCopied, setClipboardCopied] = useState(false);
   const [onlyComments, setOnlyComments] = useState(false);
+
+  const fileExtension = getFileExtensionLC(name);
+
   return (
     <ResourceRenderer
       key={id}
@@ -111,7 +116,7 @@ const SourceCodeBox = ({
                 />
               )}
 
-              <code>{name}</code>
+              <code className="me-2">{name}</code>
 
               {download && (
                 <DownloadIcon
@@ -163,6 +168,17 @@ const SourceCodeBox = ({
                 </>
               )}
 
+              {setHighlightOverride && (
+                <SourceCodeHighlightingSelector
+                  id={`${id}-highlighting`}
+                  extension={fileExtension}
+                  initialMode={highlightOverrides[fileExtension]}
+                  onChange={setHighlightOverride}
+                  timid
+                  gapLeft={2}
+                />
+              )}
+
               {diffMode && (
                 <>
                   <CodeCompareIcon
@@ -273,7 +289,7 @@ const SourceCodeBox = ({
                 oldValue={normalizeLineEndings(content.content)}
                 newValue={normalizeLineEndings(secondContent.content)}
                 splitView={true}
-                renderContent={diffViewHighlightSyntax(getPrismModeFromExtension(getFileExtensionLC(name)))}
+                renderContent={diffViewHighlightSyntax(getPrismModeFromExtension(fileExtension))}
                 compareMethod={DiffMethod.WORDS_WITH_SPACE}
               />
             </div>
@@ -291,6 +307,7 @@ const SourceCodeBox = ({
               removeComment={removeComment}
               reviewClosed={reviewClosed}
               onlyComments={reviewClosed && onlyComments}
+              highlightOverrides={highlightOverrides}
             />
           )}
         </Box>
@@ -319,6 +336,8 @@ SourceCodeBox.propTypes = {
   reviewClosed: PropTypes.bool,
   collapsable: PropTypes.bool,
   isOpen: PropTypes.bool,
+  highlightOverrides: PropTypes.object,
+  setHighlightOverride: PropTypes.func,
 };
 
 export default SourceCodeBox;
diff --git a/src/components/helpers/SourceCodeViewer/SourceCodeHighlightingSelector.js b/src/components/helpers/SourceCodeViewer/SourceCodeHighlightingSelector.js
new file mode 100644
index 000000000..015a128a9
--- /dev/null
+++ b/src/components/helpers/SourceCodeViewer/SourceCodeHighlightingSelector.js
@@ -0,0 +1,149 @@
+import React, { useState, useRef, useEffect } from 'react';
+import PropTypes from 'prop-types';
+import { FormattedMessage } from 'react-intl';
+import { Overlay, Popover, FormSelect, ButtonGroup } from 'react-bootstrap';
+
+import Button from '../../widgets/TheButton';
+import Icon, { CloseIcon, RefreshIcon, SaveIcon } from '../../icons';
+
+import { getPrismModeFromExtension, PRISM_SUPPORTED_LANGUAGES } from '../../helpers/syntaxHighlighting.js';
+
+export const localStorageHighlightOverridesKey = 'SourceCodeViewer.highlightOverrides';
+
+const SourceCodeHighlightingSelector = ({
+  id,
+  fullButton = false,
+  extension,
+  initialMode = null,
+  onChange,
+  ...props
+}) => {
+  const defaultMode = getPrismModeFromExtension(extension);
+  const target = useRef(null);
+  const [visible, setVisible] = useState(false);
+  const [selectedMode, setSelectedMode] = useState(initialMode !== null ? initialMode : defaultMode);
+
+  useEffect(() => {
+    setSelectedMode(initialMode !== null ? initialMode : defaultMode);
+  }, [initialMode, extension]);
+
+  const clickHandler = ev => {
+    ev.stopPropagation();
+    setVisible(!visible);
+  };
+
+  const changeHandler = ev => {
+    setSelectedMode(ev.target.value);
+  };
+
+  return (
+    <>
+      {fullButton ? (
+        <Button {...props} onClick={clickHandler} ref={target}>
+          <Icon icon="highlighter" gapRight={2} />
+          {(initialMode !== null ? initialMode : defaultMode) || (
+            <FormattedMessage id="app.solutionSourceCodes.noHighlighting" defaultMessage="no highlighting" />
+          )}
+        </Button>
+      ) : (
+        <Icon icon="highlighter" {...props} onClick={clickHandler} ref={target} />
+      )}
+
+      <Overlay target={target.current} show={visible} placement="bottom">
+        {props => (
+          <Popover id={id} onClick={ev => ev.stopPropagation()} className="highlighting-selector" {...props}>
+            <Popover.Header>
+              {extension ? (
+                <>
+                  <FormattedMessage
+                    id="app.solutionSourceCodes.highlightingTitle"
+                    defaultMessage="Highlighting for files with extension"
+                  />{' '}
+                  <code>*.{extension}</code>
+                </>
+              ) : (
+                <FormattedMessage
+                  id="app.solutionSourceCodes.highlightingTitleNoExtension"
+                  defaultMessage="Highlighting for files without extension"
+                />
+              )}
+            </Popover.Header>
+            <Popover.Body className="text-center">
+              <FormSelect onChange={changeHandler} value={selectedMode}>
+                <option value="" className={selectedMode === '' ? 'fw-bold text-primary' : 'fw-italic text-muted'}>
+                  [<FormattedMessage id="app.solutionSourceCodes.noHighlighting" defaultMessage="no highlighting" />]
+                  {defaultMode === '' && (
+                    <>
+                      {' ('}
+                      <FormattedMessage id="generic.default" defaultMessage="default" />
+                      {')'}
+                    </>
+                  )}
+                </option>
+                {PRISM_SUPPORTED_LANGUAGES.map(lang => (
+                  <option
+                    value={lang}
+                    key={lang}
+                    className={lang === defaultMode || lang === selectedMode ? 'fw-bold text-primary' : ''}>
+                    {lang}
+                    {lang === defaultMode && (
+                      <>
+                        {' ('}
+                        <FormattedMessage id="generic.default" defaultMessage="default" />
+                        {')'}
+                      </>
+                    )}
+                  </option>
+                ))}
+              </FormSelect>
+
+              <ButtonGroup className="mt-3">
+                <Button
+                  variant="success"
+                  size="sm"
+                  onClick={() => {
+                    onChange(extension, selectedMode !== defaultMode ? selectedMode : null);
+                    setVisible(false);
+                  }}>
+                  <SaveIcon gapRight={2} />
+                  <FormattedMessage id="generic.save" defaultMessage="Save" />
+                </Button>
+                {selectedMode !== defaultMode && (
+                  <Button
+                    variant="danger"
+                    size="sm"
+                    onClick={() => {
+                      setSelectedMode(defaultMode);
+                      onChange(extension, null);
+                    }}>
+                    <RefreshIcon gapRight={2} />
+                    <FormattedMessage id="generic.reset" defaultMessage="Reset" />
+                  </Button>
+                )}
+                <Button
+                  variant="secondary"
+                  size="sm"
+                  onClick={() => {
+                    setVisible(false);
+                  }}>
+                  <CloseIcon gapRight={2} />
+                  <FormattedMessage id="generic.close" defaultMessage="Close" />
+                </Button>
+              </ButtonGroup>
+            </Popover.Body>
+          </Popover>
+        )}
+      </Overlay>
+    </>
+  );
+};
+
+SourceCodeHighlightingSelector.propTypes = {
+  id: PropTypes.string.isRequired,
+  fullButton: PropTypes.bool,
+  extension: PropTypes.string.isRequired,
+  initialMode: PropTypes.string,
+  onChange: PropTypes.func.isRequired,
+};
+
+export default SourceCodeHighlightingSelector;
diff --git a/src/components/helpers/SourceCodeViewer/SourceCodeViewer.css b/src/components/helpers/SourceCodeViewer/SourceCodeViewer.css
index 3103baf8e..a16d4af82 100644
--- a/src/components/helpers/SourceCodeViewer/SourceCodeViewer.css
+++ b/src/components/helpers/SourceCodeViewer/SourceCodeViewer.css
@@ -156,3 +156,7 @@ pre .sourceCodeViewerComments, code .sourceCodeViewerComments {
 .sourceCodeViewer.addComment .scvAddButton:hover::before {
   opacity: 1;
 }
+
+.popover.highlighting-selector {
+  --bs-popover-max-width: 400px;
+}
diff --git a/src/components/helpers/SourceCodeViewer/SourceCodeViewer.js b/src/components/helpers/SourceCodeViewer/SourceCodeViewer.js
index 1388f1c06..827b2f1c5 100644
--- a/src/components/helpers/SourceCodeViewer/SourceCodeViewer.js
+++ b/src/components/helpers/SourceCodeViewer/SourceCodeViewer.js
@@ -7,7 +7,7 @@ import 'prismjs/themes/prism.css';
 
 import ReviewCommentForm, { newCommentFormInitialValues } from '../../forms/ReviewCommentForm';
 import { getPrismModeFromExtension } from '../../helpers/syntaxHighlighting.js';
-import { getFileExtensionLC, canUseDOM } from '../../../helpers/common.js';
+import { getFileExtensionLC, canUseDOM, EMPTY_OBJ } from '../../../helpers/common.js';
 
 import SourceCodeComment from './SourceCodeComment.js';
 import './SourceCodeViewer.css';
@@ -196,10 +196,17 @@ class SourceCodeViewer extends React.Component {
   });
 
   render() {
-    const { name, content = '', addComment } = this.props;
+    const { name, content = '', addComment, highlightOverrides = EMPTY_OBJ } = this.props;
+
+    const extension = getFileExtensionLC(name);
+    const language =
+      highlightOverrides[extension] !== undefined
+        ? highlightOverrides[extension]
+        : getPrismModeFromExtension(extension);
+
     return canUseDOM ? (
       <SyntaxHighlighter
-        language={getPrismModeFromExtension(getFileExtensionLC(name))}
+        language={language}
         style={vs}
         className={
           addComment && !this.props.onlyComments && !this.state.activeLine
@@ -234,6 +241,7 @@ SourceCodeViewer.propTypes = {
   restrictCommentAuthor: PropTypes.string,
   reviewClosed: PropTypes.bool,
   onlyComments: PropTypes.bool,
+  highlightOverrides: PropTypes.object,
 };
 
 export default SourceCodeViewer;
diff --git a/src/components/helpers/SourceCodeViewer/index.js b/src/components/helpers/SourceCodeViewer/index.js
index 7c056299f..f034ea2dd 100644
--- a/src/components/helpers/SourceCodeViewer/index.js
+++ b/src/components/helpers/SourceCodeViewer/index.js
@@ -1,2 +1,6 @@
 export { default } from './SourceCodeViewer.js';
 export { default as SourceCodeComment } from './SourceCodeComment.js';
+export {
+  default as SourceCodeHighlightingSelector,
+  localStorageHighlightOverridesKey,
+} from './SourceCodeHighlightingSelector.js';
diff --git a/src/components/helpers/syntaxHighlighting.js b/src/components/helpers/syntaxHighlighting.js
index 015135695..0e301d42b 100644
--- a/src/components/helpers/syntaxHighlighting.js
+++ b/src/components/helpers/syntaxHighlighting.js
@@ -30,16 +30,18 @@ const aceMapping = {
   html: 'html',
 };
 
-export const createExtensionTranslator = mapping => ext => {
-  ext = ext.trim().toLowerCase();
-  if (ext === '') {
-    return mapping.makefile; // makefile has no extension
-  } else if (mapping[ext]) {
-    return mapping[ext]; // mapping found
-  } else {
-    return mapping.cpp; // C/C++ is default
-  }
-};
+export const createExtensionTranslator =
+  (mapping, defaultDefault = null) =>
+  (ext, defaultValue = defaultDefault) => {
+    ext = ext.trim().toLowerCase();
+    if (ext === '') {
+      return mapping.makefile; // makefile has no extension
+    } else if (mapping[ext]) {
+      return mapping[ext]; // mapping found
+    } else {
+      return defaultValue;
+    }
+  };
 
 const prismMapping = {
   ...commonMapping,
@@ -61,5 +63,302 @@ const prismMapping = {
   xml: 'markup',
 };
 
-export const getAceModeFromExtension = createExtensionTranslator(aceMapping);
-export const getPrismModeFromExtension = createExtensionTranslator(prismMapping);
+export const getAceModeFromExtension = createExtensionTranslator(aceMapping, aceMapping.cpp);
+export const getPrismModeFromExtension = createExtensionTranslator(prismMapping, null);
+
+export const PRISM_SUPPORTED_LANGUAGES = [
+  'abap',
+  'abnf',
+  'actionscript',
+  'ada',
+  'agda',
+  'al',
+  'antlr4',
+  'apacheconf',
+  'apex',
+  'apl',
+  'applescript',
+  'aql',
+  'arduino',
+  'arff',
+  'armasm',
+  'arturo',
+  'asciidoc',
+  'asm6502',
+  'asmatmel',
+  'aspnet',
+  'autohotkey',
+  'autoit',
+  'avisynth',
+  'awk',
+  'bash',
+  'basic',
+  'batch',
+  'bbcode',
+  'bbj',
+  'bicep',
+  'birb',
+  'bison',
+  'bnf',
+  'bqn',
+  'brainfuck',
+  'brightscript',
+  'bro',
+  'bsl',
+  'c',
+  'cfscript',
+  'chaiscript',
+  'cil',
+  'cilkc',
+  'cilkcpp',
+  'clike',
+  'clojure',
+  'cmake',
+  'cobol',
+  'coffeescript',
+  'concurnas',
+  'cooklang',
+  'coq',
+  'cpp',
+  'crystal',
+  'csharp',
+  'cshtml',
+  'csp',
+  'cssExtras',
+  'css',
+  'csv',
+  'cue',
+  'cypher',
+  'd',
+  'dart',
+  'dataweave',
+  'dax',
+  'dhall',
+  'diff',
+  'django',
+  'dnsZoneFile',
+  'docker',
+  'dot',
+  'ebnf',
+  'editorconfig',
+  'eiffel',
+  'ejs',
+  'elixir',
+  'elm',
+  'erb',
+  'erlang',
+  'etlua',
+  'excelFormula',
+  'factor',
+  'falselang',
+  'firestoreSecurityRules',
+  'flow',
+  'fortran',
+  'fsharp',
+  'ftl',
+  'gap',
+  'gcode',
+  'gdscript',
+  'gedcom',
+  'gettext',
+  'gherkin',
+  'git',
+  'glsl',
+  'gml',
+  'gn',
+  'goModule',
+  'go',
+  'gradle',
+  'graphql',
+  'groovy',
+  'haml',
+  'handlebars',
+  'haskell',
+  'haxe',
+  'hcl',
+  'hlsl',
+  'hoon',
+  'hpkp',
+  'hsts',
+  'http',
+  'ichigojam',
+  'icon',
+  'icuMessageFormat',
+  'idris',
+  'iecst',
+  'ignore',
+  'inform7',
+  'ini',
+  'io',
+  'j',
+  'java',
+  'javadoc',
+  'javadoclike',
+  'javascript',
+  'javastacktrace',
+  'jexl',
+  'jolie',
+  'jq',
+  'jsExtras',
+  'jsTemplates',
+  'jsdoc',
+  'json',
+  'json5',
+  'jsonp',
+  'jsstacktrace',
+  'jsx',
+  'julia',
+  'keepalived',
+  'keyman',
+  'kotlin',
+  'kumir',
+  'kusto',
+  'latex',
+  'latte',
+  'less',
+  'lilypond',
+  'linkerScript',
+  'liquid',
+  'lisp',
+  'livescript',
+  'llvm',
+  'log',
+  'lolcode',
+  'lua',
+  'magma',
+  'makefile',
+  'markdown',
+  'markupTemplating',
+  'markup',
+  'mata',
+  'matlab',
+  'maxscript',
+  'mel',
+  'mermaid',
+  'metafont',
+  'mizar',
+  'mongodb',
+  'monkey',
+  'moonscript',
+  'n1ql',
+  'n4js',
+  'nand2tetrisHdl',
+  'naniscript',
+  'nasm',
+  'neon',
+  'nevod',
+  'nginx',
+  'nim',
+  'nix',
+  'nsis',
+  'objectivec',
+  'ocaml',
+  'odin',
+  'opencl',
+  'openqasm',
+  'oz',
+  'parigp',
+  'parser',
+  'pascal',
+  'pascaligo',
+  'pcaxis',
+  'peoplecode',
+  'perl',
+  'php',
+  'phpdoc',
+  'plantUml',
+  'plsql',
+  'powerquery',
+  'powershell',
+  'processing',
+  'prolog',
+  'promql',
+  'properties',
+  'protobuf',
+  'psl',
+  'pug',
+  'puppet',
+  'pure',
+  'purebasic',
+  'purescript',
+  'python',
+  'q',
+  'qml',
+  'qore',
+  'qsharp',
+  'r',
+  'racket',
+  'reason',
+  'regex',
+  'rego',
+  'renpy',
+  'rescript',
+  'rest',
+  'rip',
+  'roboconf',
+  'robotframework',
+  'ruby',
+  'rust',
+  'sas',
+  'sass',
+  'scala',
+  'scheme',
+  'scss',
+  'shellSession',
+  'smali',
+  'smalltalk',
+  'smarty',
+  'sml',
+  'solidity',
+  'soy',
+  'sparql',
+  'splunkSpl',
+  'sqf',
+  'sql',
+  'squirrel',
+  'stan',
+  'stata',
+  'stylus',
+  'supercollider',
+  'swift',
+  'systemd',
+  't4Cs',
+  't4Templating',
+  't4Vb',
+  'tap',
+  'tcl',
+  'textile',
+  'toml',
+  'tremor',
+  'tsx',
+  'tt2',
+  'turtle',
+  'twig',
+  'typescript',
+  'typoscript',
+  'unrealscript',
+  'uorazor',
+  'uri',
+  'v',
+  'vala',
+  'vbnet',
+  'velocity',
+  'verilog',
+  'vhdl',
+  'vim',
+  'visualBasic',
+  'warpscript',
+  'wasm',
+  'webIdl',
+  'wgsl',
+  'wiki',
+  'wolfram',
+  'wren',
+  'xeora',
+  'xmlDoc',
+  'xojo',
+  'xquery',
+  'yaml',
+  'yang',
+  'zig',
+];
diff --git a/src/containers/SourceCodeViewerContainer/SourceCodeViewerContainer.js b/src/containers/SourceCodeViewerContainer/SourceCodeViewerContainer.js
index 59390d34f..d865dd133 100644
--- a/src/containers/SourceCodeViewerContainer/SourceCodeViewerContainer.js
+++ b/src/containers/SourceCodeViewerContainer/SourceCodeViewerContainer.js
@@ -4,18 +4,25 @@ import ImmutablePropTypes from 'react-immutable-proptypes';
 import { connect } from 'react-redux';
 import { FormattedMessage } from 'react-intl';
 import { Dropdown, DropdownButton, Modal } from 'react-bootstrap';
+import { CopyToClipboard } from 'react-copy-to-clipboard';
 import { lruMemoize } from 'reselect';
 
 import Button from '../../components/widgets/TheButton';
 import Callout from '../../components/widgets/Callout';
-import { DownloadIcon, LoadingIcon } from '../../components/icons';
+import { CopyIcon, CopySuccessIcon, DownloadIcon, LoadingIcon } from '../../components/icons';
 import { download } from '../../redux/modules/files.js';
 import { fetchContentIfNeeded } from '../../redux/modules/filesContent.js';
 import { getFilesContent } from '../../redux/selectors/files.js';
 import ResourceRenderer from '../../components/helpers/ResourceRenderer';
-import SourceCodeViewer from '../../components/helpers/SourceCodeViewer';
+import SourceCodeViewer, {
+  SourceCodeHighlightingSelector,
+  localStorageHighlightOverridesKey,
+} from '../../components/helpers/SourceCodeViewer';
+
 import DownloadSolutionArchiveContainer from '../DownloadSolutionArchiveContainer';
 import UsersNameContainer from '../UsersNameContainer';
+import { getFileExtensionLC } from '../../helpers/common.js';
+import { storageGetItem, storageSetItem } from '../../helpers/localStorage.js';
 
 import * as styles from './sourceCode.less';
 
@@ -40,10 +47,15 @@ const preprocessFiles = lruMemoize(files =>
 );
 
 class SourceCodeViewerContainer extends Component {
+  state = { clipboardCopied: false, highlightOverrides: {} };
+
   componentDidMount() {
     const { fileId, loadAsync } = this.props;
     if (fileId !== null) {
       loadAsync();
+      this.setState({
+        highlightOverrides: storageGetItem(localStorageHighlightOverridesKey, {}),
+      });
     }
   }
 
@@ -53,9 +65,21 @@ class SourceCodeViewerContainer extends Component {
       (this.props.fileId !== prevProps.fileId || this.props.zipEntry !== prevProps.zipEntry)
     ) {
       this.props.loadAsync();
+      this.setState({
+        highlightOverrides: storageGetItem(localStorageHighlightOverridesKey, {}),
+      });
     }
   }
 
+  setHighlightOverride = (extension, mode) => {
+    const { [extension]: _, ...newOverrides } = this.state.highlightOverrides;
+    if (mode || mode === '') {
+      newOverrides[extension] = mode;
+    }
+    this.setState({ highlightOverrides: newOverrides });
+    storageSetItem(localStorageHighlightOverridesKey, newOverrides);
+  };
+
   render() {
     const {
       show,
@@ -72,6 +96,8 @@ class SourceCodeViewerContainer extends Component {
       submittedBy = null,
     } = this.props;
 
+    const fileExtension = getFileExtensionLC(fileName);
+
     return (
       <ResourceRenderer
         loading={
@@ -92,14 +118,20 @@ class SourceCodeViewerContainer extends Component {
         }
         resource={content}>
         {content => (
-          <Modal show={show} onHide={onHide} onEscapeKeyDown={onHide} dialogClassName={styles.modal} size="xl">
+          <Modal
+            show={show}
+            onHide={onHide}
+            onEscapeKeyDown={onHide}
+            dialogClassName={styles.modal}
+            size="xl"
+            enforceFocus={false}>
             <Modal.Header closeButton>
               <ResourceRenderer resource={files}>
                 {files => (
                   <>
                     <DropdownButton
                       size="sm"
-                      className="shadow font-monospace"
+                      className="shadow font-monospace me-2"
                       title={fileName}
                       variant="outline-secondary">
                       {preprocessFiles(files).map(f => (
@@ -113,11 +145,36 @@ class SourceCodeViewerContainer extends Component {
                       ))}
                     </DropdownButton>
 
-                    <Button size="sm" className="mx-2 " onClick={() => download(fileId, zipEntry)}>
+                    <SourceCodeHighlightingSelector
+                      id="highlighting"
+                      fullButton
+                      size="sm"
+                      className="me-2"
+                      variant="outline-secondary"
+                      extension={fileExtension}
+                      initialMode={this.state.highlightOverrides[fileExtension]}
+                      onChange={this.setHighlightOverride}
+                    />
+
+                    <Button size="sm" className="me-2" onClick={() => download(fileId, zipEntry)}>
                       <DownloadIcon gapRight={2} />
                       <FormattedMessage id="app.sourceCodeViewer.downloadButton" defaultMessage="Download file" />
                     </Button>
 
+                    {!content.tooLarge && !content.malformedCharacters && (
+                      <CopyToClipboard
+                        text={content.content}
+                        onCopy={() => {
+                          this.setState({ clipboardCopied: true });
+                          window.setTimeout(() => this.setState({ clipboardCopied: false }), 2000);
+                        }}>
+                        <Button size="sm" className="me-2">
+                          {this.state.clipboardCopied ? <CopySuccessIcon gapRight={2} /> : <CopyIcon gapRight={2} />}
+                          <FormattedMessage id="generic.copyToClipboard" defaultMessage="Copy to clipboard" />
+                        </Button>
+                      </CopyToClipboard>
+                    )}
+
                     {files.length > 0 && (
                       <DownloadSolutionArchiveContainer
                         solutionId={solutionId}
@@ -163,7 +220,13 @@ class SourceCodeViewerContainer extends Component {
               {content.malformedCharacters ? (
                 <pre className="border-top">{content.content}</pre>
               ) : (
-                <SourceCodeViewer id={fileId} content={content.content} name={fileName} solutionId={solutionId} />
+                <SourceCodeViewer
+                  id={fileId}
+                  content={content.content}
+                  name={fileName}
+                  solutionId={solutionId}
+                  highlightOverrides={this.state.highlightOverrides}
+                />
               )}
               <div className="border-top pt-1 bg-light rounded-bottom"></div>
             </Modal.Body>
diff --git a/src/locales/cs.json b/src/locales/cs.json
index 3e9478566..ea9186c6f 100644
--- a/src/locales/cs.json
+++ b/src/locales/cs.json
@@ -1894,6 +1894,8 @@
   "app.solutionSourceCodes.diffModal.title": "Porovnat dvě řešení a zobrazit rozdíly",
   "app.solutionSourceCodes.downloadTooltip": "Stáhnout soubor",
   "app.solutionSourceCodes.fullWidthTooltip": "Povolit celou šířku slouců, i když celková šíře boxu překročí šířku obrazovky.",
+  "app.solutionSourceCodes.highlightingTitle": "Zvýraznění syntaxe pro soubory s příponou",
+  "app.solutionSourceCodes.highlightingTitleNoExtension": "Zvýraznění syntaxe pro soubory bez přípony",
   "app.solutionSourceCodes.isBeingComparedWith": "... je porovnáváno s ...",
   "app.solutionSourceCodes.left": "Nalevo",
   "app.solutionSourceCodes.malformedTooltip": "Tento soubor neobsahuje běžný text v kódování UTF-8, takže není možne jej zobrazit jako zdrojový kód.",
@@ -1902,6 +1904,7 @@
   "app.solutionSourceCodes.mappingModal.resetButton": "Výchozí mapování",
   "app.solutionSourceCodes.mappingModal.title": "Upravit mapování porovnávaných souborů",
   "app.solutionSourceCodes.noDiffWithFile": "žádný odpovídající soubor pro porovnání nebyl nalezen",
+  "app.solutionSourceCodes.noHighlighting": "žádné zvýraznění",
   "app.solutionSourceCodes.restrictWidthTooltip": "Omezit šířky sloupců, aby každý zabíral polovinu obrazovky.",
   "app.solutionSourceCodes.reviewClosedAuthorInfoNoIssues": "Vaše řešení bylo revidováno a nejsou k němu vedeny žádné připomínky.",
   "app.solutionSourceCodes.reviewClosedAuthorInfoWithIssues": "Vaše řešení bylo revidováno. Máte celkem {issues} {issues, plural, one {připomínku} =2 {připomínky} =3 {připomínky} =4 {připomínky} other {připomínek}} k vyřešení.",
@@ -2101,6 +2104,7 @@
   "generic.createdAt": "Vytvořeno",
   "generic.creating": "Vytváření...",
   "generic.creationFailed": "Vytvoření se nezdařilo. Prosíme, opakujte akci později.",
+  "generic.default": "výchozí",
   "generic.delete": "Smazat",
   "generic.deleteFailed": "Smazání selhalo",
   "generic.deleted": "Smazáno",
diff --git a/src/locales/en.json b/src/locales/en.json
index e7041788a..18deee345 100644
--- a/src/locales/en.json
+++ b/src/locales/en.json
@@ -1894,6 +1894,8 @@
   "app.solutionSourceCodes.diffModal.title": "Compare two solutions and display differences",
   "app.solutionSourceCodes.downloadTooltip": "Download the file.",
   "app.solutionSourceCodes.fullWidthTooltip": "Enable full width of each column even if the box exceeds the screen width.",
+  "app.solutionSourceCodes.highlightingTitle": "Highlighting for files with extension",
+  "app.solutionSourceCodes.highlightingTitleNoExtension": "Highlighting for files without extension",
   "app.solutionSourceCodes.isBeingComparedWith": "... is being compared with ...",
   "app.solutionSourceCodes.left": "Left side",
   "app.solutionSourceCodes.malformedTooltip": "The file is not a valid UTF-8 text file so it cannot be properly displayed as a source code.",
@@ -1902,6 +1904,7 @@
   "app.solutionSourceCodes.mappingModal.resetButton": "Reset mapping",
   "app.solutionSourceCodes.mappingModal.title": "Adjust mapping of compared files",
   "app.solutionSourceCodes.noDiffWithFile": "no corresponding file for the comparison found",
+  "app.solutionSourceCodes.noHighlighting": "no highlighting",
   "app.solutionSourceCodes.restrictWidthTooltip": "Restrict the width of each column to the half of the screen.",
   "app.solutionSourceCodes.reviewClosedAuthorInfoNoIssues": "Your solution was reviewed and no issues were reported.",
   "app.solutionSourceCodes.reviewClosedAuthorInfoWithIssues": "Your solution was reviewed. You have {issues} {issues, plural, one {issue} other {issues}} to fix.",
@@ -2101,6 +2104,7 @@
   "generic.createdAt": "Created at",
   "generic.creating": "Creating...",
   "generic.creationFailed": "Creation failed. Please try again later.",
+  "generic.default": "default",
   "generic.delete": "Delete",
   "generic.deleteFailed": "Delete Failed",
   "generic.deleted": "Deleted",
@@ -2178,4 +2182,4 @@
   "recodex-judge-shuffle-all": "Unordered-tokens-and-rows judge",
   "recodex-judge-shuffle-newline": "Unordered-tokens judge (ignoring ends of lines)",
   "recodex-judge-shuffle-rows": "Unordered-rows judge"
-}
+}
\ No newline at end of file
diff --git a/src/pages/SolutionSourceCodes/SolutionSourceCodes.js b/src/pages/SolutionSourceCodes/SolutionSourceCodes.js
index 7e4177356..184dc4b30 100644
--- a/src/pages/SolutionSourceCodes/SolutionSourceCodes.js
+++ b/src/pages/SolutionSourceCodes/SolutionSourceCodes.js
@@ -27,6 +27,7 @@ import ReviewSummary from '../../components/Solutions/ReviewSummary';
 import RecentlyVisited from '../../components/Solutions/RecentlyVisited';
 import { registerSolutionVisit } from '../../components/Solutions/RecentlyVisited/functions.js';
 import Callout from '../../components/widgets/Callout';
+import { localStorageHighlightOverridesKey } from '../../components/helpers/SourceCodeViewer';
 import SolutionActionsContainer from '../../containers/SolutionActionsContainer';
 import SolutionReviewRequestButtonContainer from '../../containers/SolutionReviewRequestButtonContainer';
 import CommentThreadContainer from '../../containers/CommentThreadContainer';
@@ -58,12 +59,11 @@ import { loggedUserIsPrimaryAdminOfSelector } from '../../redux/selectors/usersG
 
 import { storageGetItem, storageSetItem, storageRemoveItem } from '../../helpers/localStorage.js';
 import { isSupervisorRole } from '../../components/helpers/usersRoles.js';
-import { hasPermissions, hasOneOfPermissions, isEmptyObject, EMPTY_ARRAY } from '../../helpers/common.js';
-import { preprocessFiles, associateFilesForDiff, getRevertedMapping, groupReviewCommentPerFile } from './functions.js';
-
 import { isStudentLocked } from '../../components/helpers/exams.js';
 import withLinks from '../../helpers/withLinks.js';
 import withRouter, { withRouterProps } from '../../helpers/withRouter.js';
+import { hasPermissions, hasOneOfPermissions, isEmptyObject, EMPTY_ARRAY } from '../../helpers/common.js';
+import { preprocessFiles, associateFilesForDiff, getRevertedMapping, groupReviewCommentPerFile } from './functions.js';
 
 const fileNameAndEntry = file => [file.parentId || file.id, file.entryName || null];
 
@@ -78,6 +78,7 @@ class SolutionSourceCodes extends Component {
     mappingDialogDiffWith: null,
     diffMappings: {},
     commentsOpen: false,
+    highlightOverrides: {},
   };
 
   static loadAsync = ({ solutionId, assignmentId, secondSolutionId }, dispatch) =>
@@ -122,10 +123,12 @@ class SolutionSourceCodes extends Component {
 
     const lsKey = this.getDiffMappingsLocalStorageKey();
     if (lsKey) {
-      this.setState({
-        diffMappings: storageGetItem(lsKey, {}),
-      });
+      this.setState({ diffMappings: storageGetItem(lsKey, {}) });
     }
+
+    this.setState({
+      highlightOverrides: storageGetItem(localStorageHighlightOverridesKey, {}),
+    });
   }
 
   componentDidUpdate(prevProps) {
@@ -137,10 +140,12 @@ class SolutionSourceCodes extends Component {
 
       const lsKey = this.getDiffMappingsLocalStorageKey();
       if (lsKey) {
-        this.setState({
-          diffMappings: storageGetItem(lsKey, {}),
-        });
+        this.setState({ diffMappings: storageGetItem(lsKey, {}) });
       }
+
+      this.setState({
+        highlightOverrides: storageGetItem(localStorageHighlightOverridesKey, {}),
+      });
     }
   }
 
@@ -213,6 +218,15 @@ class SolutionSourceCodes extends Component {
     }
   };
 
+  setHighlightOverride = (extension, mode) => {
+    const { [extension]: _, ...newOverrides } = this.state.highlightOverrides;
+    if (mode || mode === '') {
+      newOverrides[extension] = mode;
+    }
+    this.setState({ highlightOverrides: newOverrides });
+    storageSetItem(localStorageHighlightOverridesKey, newOverrides);
+  };
+
   render() {
     const {
       assignment,
@@ -520,6 +534,8 @@ class SolutionSourceCodes extends Component {
                                 removeComment={
                                   canUpdateComments && hasPermissions(solution, 'review') ? removeComment : null
                                 }
+                                highlightOverrides={this.state.highlightOverrides}
+                                setHighlightOverride={this.setHighlightOverride}
                               />
                             ))}