diff --git a/NEWS.md b/NEWS.md
index 71d932d6b1..d78140f474 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -26,6 +26,10 @@ See the [plotly.js releases page](https://github.com/plotly/plotly.js/releases)
 ## Bug fixes
 
 * `plotly_build()` now works with `ggmatrix` objects (e.g., from `GGally::ggpairs()`). (#2447)
+* Cross-trace layout attributes (`bargroupgap`, `boxmode`, `violingap`, etc.) no longer produce errant warnings. (#2458)
+* `ggplotly()` now correctly uses custom legend labels from `scale_*_manual(labels = ...)`. (#2420)
+* `ggplotly()` with `dynamicTicks = TRUE` no longer errors on grouped `geom_line()` plots. (#2462)
+* `plot_ly()` with color mapping no longer resets Date/POSIXct x-axis values to 1970. (#2446)
 * Closed #2415: `ggplotly()` now shows variables named 'group' in tooltips when mapped to aesthetics like `colour`.
 * Closed #2455, #2460: `ggplotly()` no longer creates empty shapes when `panel.border` is `element_blank()` (ggplot2 4.0.0 compatibility).
 * Closed #2466: `ggplotly()` no longer errors when `scale_*_manual()` has unused aesthetics (e.g., `aesthetics = c("colour", "fill")` when only colour is used).
diff --git a/R/ggplotly.R b/R/ggplotly.R
index a37804dd9e..e97a7e8442 100644
--- a/R/ggplotly.R
+++ b/R/ggplotly.R
@@ -845,10 +845,12 @@ gg2list <- function(p, width = NULL, height = NULL,
       
       # inverse transform categorical data based on tickvals/ticktext
       if (isDiscreteType) {
-        traces <- lapply(traces, function(tr) { 
+        traces <- lapply(traces, function(tr) {
           # map x/y trace data back to the 'closest' ticktext label
           # http://r.789695.n4.nabble.com/check-for-nearest-value-in-a-vector-td4369339.html
           tr[[xy]]<- vapply(tr[[xy]], function(val) {
+            # NA values (e.g., geom_line gaps) should remain NA
+            if (is.na(val)) return(NA_character_)
             with(axisObj, ticktext[[which.min(abs(tickvals - val))]])
           }, character(1))
           tr
diff --git a/R/layers2traces.R b/R/layers2traces.R
index 181ef72909..5717b9adb0 100644
--- a/R/layers2traces.R
+++ b/R/layers2traces.R
@@ -139,8 +139,28 @@ layers2traces <- function(data, prestats_data, layout, p) {
     # note: this allows us to control multiple traces from one legend entry
     if (any(split_legend %in% names(d))) {
       nms <- strsplit(names(trs), separator, fixed = TRUE)
+      # Build mapping from domain values to scale labels (for custom labels)
+      legend_aes <- sub("_plotlyDomain$", "", split_legend)
+      value_to_label <- list()
+      for (aes in legend_aes) {
+        sc <- discreteScales[[aes]]
+        if (!is.null(sc)) {
+          breaks <- tryCatch(sc$get_breaks(), error = function(e) NULL)
+          labels <- tryCatch(sc$get_labels(), error = function(e) NULL)
+          if (length(breaks) > 0 && length(breaks) == length(labels)) {
+            value_to_label[[aes]] <- setNames(as.character(labels), as.character(breaks))
+          }
+        }
+      }
       nms <- vapply(nms, function(x) {
         y <- unique(x[seq_along(split_legend)])
+        # Map domain values to scale labels if custom labels exist
+        for (j in seq_along(y)) {
+          aes <- legend_aes[j]
+          if (aes %in% names(value_to_label) && y[j] %in% names(value_to_label[[aes]])) {
+            y[j] <- value_to_label[[aes]][y[j]]
+          }
+        }
         if (length(y) > 1) paste0("(", paste(y, collapse = ","), ")") else y
       }, character(1))
       trs <- Map(function(x, y) {
diff --git a/R/plotly_build.R b/R/plotly_build.R
index 3bdd432601..acfacd0450 100644
--- a/R/plotly_build.R
+++ b/R/plotly_build.R
@@ -877,9 +877,10 @@ map_color <- function(traces, stroke = FALSE, title = "", colorway, na.color = "
     # add an "empty" trace with the colorbar
     colorObj$color <- rng
     colorObj$showscale <- default(TRUE)
+    # Use do.call(c, ...) instead of unlist() to preserve Date/POSIXct classes
     colorBarTrace <- list(
-      x = range(unlist(lapply(traces, "[[", "x")), na.rm = TRUE),
-      y = range(unlist(lapply(traces, "[[", "y")), na.rm = TRUE),
+      x = range(do.call(c, lapply(traces, "[[", "x")), na.rm = TRUE),
+      y = range(do.call(c, lapply(traces, "[[", "y")), na.rm = TRUE),
       type = if (any(types %in% glTypes())) "scattergl" else "scatter",
       mode = "markers",
       opacity = 0,
@@ -890,7 +891,7 @@ map_color <- function(traces, stroke = FALSE, title = "", colorway, na.color = "
     # 3D needs a z property
     if ("scatter3d" %in% types) {
       colorBarTrace$type <- "scatter3d"
-      colorBarTrace$z <- range(unlist(lapply(traces, "[[", "z")), na.rm = TRUE)
+      colorBarTrace$z <- range(do.call(c, lapply(traces, "[[", "z")), na.rm = TRUE)
     }
     if (length(type <- intersect(c("scattergeo", "scattermapbox"), types))) {
       colorBarTrace$type <- type
diff --git a/R/utils.R b/R/utils.R
index b558e12b03..2ae386df03 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -447,9 +447,19 @@ supply_highlight_attrs <- function(p) {
 # make sure plot attributes adhere to the plotly.js schema
 verify_attr_names <- function(p) {
   # some layout attributes (e.g., [x-y]axis can have trailing numbers)
+  # Cross-trace layout attrs (bar/box/violin/funnel/waterfall) are not in the
+  # plotly.js schema's layoutAttributes, but are valid and must be whitelisted
+  cross_trace_attrs <- c(
+    "barmode", "barnorm", "bargap", "bargroupgap",
+    "boxmode", "boxgap", "boxgroupgap",
+    "violinmode", "violingap", "violingroupgap",
+    "funnelmode", "funnelgap", "funnelgroupgap",
+    "waterfallmode", "waterfallgap", "waterfallgroupgap",
+    "mapType"
+  )
   attrs_name_check(
     sub("[0-9]+$", "", names(p$x$layout)),
-    c(names(Schema$layout$layoutAttributes), c("boxmode", "barmode", "bargap", "mapType")),
+    c(names(Schema$layout$layoutAttributes), cross_trace_attrs),
     "layout"
   )
   attrs_name_check(
diff --git a/tests/testthat/test-issue-fixes.R b/tests/testthat/test-issue-fixes.R
new file mode 100644
index 0000000000..fd9f0a3757
--- /dev/null
+++ b/tests/testthat/test-issue-fixes.R
@@ -0,0 +1,150 @@
+# Tests for specific issue fixes
+
+# Issue #2458: bargroupgap and other layout attributes should not warn
+test_that("Cross-trace layout attributes do not produce warnings", {
+  p <- plot_ly(x = 1:3, y = 1:3, type = "bar")
+
+  # Bar attributes
+  expect_silent(plotly_build(layout(p, bargroupgap = 0.1)))
+  expect_silent(plotly_build(layout(p, barnorm = "fraction")))
+
+  # Box attributes
+  expect_silent(plotly_build(layout(p, boxmode = "group")))
+  expect_silent(plotly_build(layout(p, boxgap = 0.1)))
+  expect_silent(plotly_build(layout(p, boxgroupgap = 0.1)))
+
+  # Violin attributes
+  expect_silent(plotly_build(layout(p, violinmode = "group")))
+  expect_silent(plotly_build(layout(p, violingap = 0.1)))
+  expect_silent(plotly_build(layout(p, violingroupgap = 0.1)))
+
+  # Funnel attributes
+  expect_silent(plotly_build(layout(p, funnelmode = "group")))
+  expect_silent(plotly_build(layout(p, funnelgap = 0.1)))
+  expect_silent(plotly_build(layout(p, funnelgroupgap = 0.1)))
+
+  # Waterfall attributes
+  expect_silent(plotly_build(layout(p, waterfallmode = "group")))
+  expect_silent(plotly_build(layout(p, waterfallgap = 0.1)))
+  expect_silent(plotly_build(layout(p, waterfallgroupgap = 0.1)))
+})
+
+# Issue #2420: ggplotly legend should use scale labels
+test_that("ggplotly legend uses custom scale labels", {
+  d <- data.frame(X = 1:5, Y = 1:5)
+
+  # Test with scale_color_manual labels
+
+  gg <- ggplot(d, aes(x = X, y = Y, col = "value1")) +
+    geom_point() +
+    scale_color_manual(values = c("blue"), labels = c("Custom Label"))
+
+  p <- ggplotly(gg)
+  built <- plotly_build(p)
+
+  # The trace name should be "Custom Label", not "value1"
+  expect_equal(built$x$data[[1]]$name, "Custom Label")
+  expect_equal(built$x$data[[1]]$legendgroup, "Custom Label")
+})
+
+test_that("ggplotly legend uses custom labels with multiple values", {
+  d <- data.frame(X = 1:10, Y = (1:10)^2, grp = rep(c("a", "b"), 5))
+
+  gg <- ggplot(d, aes(x = X, y = Y, col = grp)) +
+    geom_point() +
+    scale_color_manual(
+      values = c("a" = "red", "b" = "blue"),
+      labels = c("a" = "Group A", "b" = "Group B")
+    )
+
+  p <- ggplotly(gg)
+  built <- plotly_build(p)
+
+  # Get trace names
+  trace_names <- sapply(built$x$data, function(tr) tr$name)
+  trace_names <- trace_names[!is.na(trace_names)]
+
+  expect_true("Group A" %in% trace_names)
+  expect_true("Group B" %in% trace_names)
+  expect_false("a" %in% trace_names)
+  expect_false("b" %in% trace_names)
+})
+
+# Issue #2462: dynamicTicks with grouped geom_line should not error
+test_that("dynamicTicks works with grouped geom_line", {
+  df <- data.frame(
+    time = factor(rep(c("t1", "t2"), 4)),
+    value = c(1.25, 1.5, 2, 1.75, 1.25, 0.25, 3, 3.5),
+    grp = factor(rep(1:4, each = 2))
+  )
+
+  p <- ggplot(df, aes(x = time, y = value)) +
+    geom_line(aes(group = grp))
+
+  # This should not error (previously failed with "attempt to select less than one element")
+  expect_silent(built <- plotly_build(ggplotly(p, dynamicTicks = TRUE)))
+
+  # Verify the data contains NA values (from group2NA) that are preserved
+  trace_x <- built$x$data[[1]]$x
+  expect_true(any(is.na(trace_x)))
+
+  # Non-NA values should be categorical labels
+  non_na_x <- trace_x[!is.na(trace_x)]
+  expect_true(all(non_na_x %in% c("t1", "t2")))
+})
+
+# Issue #2446: Date class should be preserved in colorbar trace
+test_that("Date class is preserved in colorbar trace", {
+  df <- data.frame(
+    y = 1:10,
+    rank = sample(1:100, 10),
+    datetime = seq(as.Date("2022-01-01"), by = "day", length.out = 10)
+  )
+
+  p <- plot_ly(df, type = "scatter", mode = "markers") %>%
+    add_trace(x = ~datetime, y = ~y, color = ~rank)
+
+  built <- plotly_build(p)
+
+
+  # Find the main data trace (not the empty first trace or colorbar)
+  data_trace <- NULL
+  for (tr in built$x$data) {
+    if (!is.null(tr[["x"]]) && length(tr[["x"]]) > 2) {
+      data_trace <- tr
+      break
+    }
+  }
+
+  expect_false(is.null(data_trace))
+  expect_s3_class(data_trace[["x"]], "Date")
+
+  # The x values should be in 2022, not 1970
+  expect_true(all(data_trace[["x"]] >= as.Date("2022-01-01")))
+  expect_true(all(data_trace[["x"]] <= as.Date("2022-12-31")))
+})
+
+test_that("POSIXct class is preserved in colorbar trace", {
+  df <- data.frame(
+    y = 1:10,
+    rank = sample(1:100, 10),
+    datetime = seq(as.POSIXct("2022-01-01"), by = "day", length.out = 10)
+  )
+
+  p <- plot_ly(df, type = "scatter", mode = "markers") %>%
+    add_trace(x = ~datetime, y = ~y, color = ~rank)
+
+  built <- plotly_build(p)
+
+  # Find the main data trace
+  data_trace <- NULL
+  for (tr in built$x$data) {
+    if (!is.null(tr[["x"]]) && length(tr[["x"]]) > 2) {
+      data_trace <- tr
+      break
+    }
+  }
+
+  expect_false(is.null(data_trace))
+  expect_s3_class(data_trace[["x"]], "POSIXt")
+})