diff --git a/src/editor/core/cm/prefs.ts b/src/editor/core/cm/prefs.ts
index 333a054b..81fd80ee 100644
--- a/src/editor/core/cm/prefs.ts
+++ b/src/editor/core/cm/prefs.ts
@@ -34,6 +34,7 @@ import {
   selectLineStart,
 } from "@codemirror/commands";
 import { markdownImages } from "./markdownImages";
+import { selectionMarks } from "./selectionMarks";
 import type { EditorExtras } from "@/platform/editorSettings";
 import { openideaHighlightStyle } from "./highlight";
 import {
@@ -504,6 +505,7 @@ export function caretExtension(prefs: EditorExtras): Extension {
     // Before drawSelection: its measure request must run before the cursor layer redraws.
     a.smoothCaretMovement ? caretGlide : [],
     drawSelection({ cursorBlinkRate: a.caretBlinking ? Math.max(100, Math.min(5000, a.caretBlinkPeriod)) * 2 : 0 }),
+    selectionMarks,
     classes.length ? EditorView.editorAttributes.of({ class: classes.join(" ") }) : [],
   ];
 }
diff --git a/src/editor/core/cm/selectionMarks.test.ts b/src/editor/core/cm/selectionMarks.test.ts
new file mode 100644
index 00000000..7c3c2e77
--- /dev/null
+++ b/src/editor/core/cm/selectionMarks.test.ts
@@ -0,0 +1,57 @@
+import { afterEach, describe, expect, it } from "vitest";
+import { EditorSelection, EditorState, Prec, type Extension } from "@codemirror/state";
+import { Decoration, EditorView } from "@codemirror/view";
+import { selectionMarks } from "./selectionMarks";
+
+const views: EditorView[] = [];
+afterEach(() => views.splice(0).forEach((v) => v.destroy()));
+
+function view(doc: string, selection: EditorSelection, extensions: Extension) {
+  extensions = [EditorState.allowMultipleSelections.of(true), extensions];
+  const parent = document.createElement("div");
+  document.body.appendChild(parent);
+  const v = new EditorView({ state: EditorState.create({ doc, selection, extensions }), parent });
+  views.push(v);
+  return v;
+}
+
+/** A background mark as features add it (lint range, find match, usage, semantic bg…). */
+const backgroundMark = (cls: string, from: number, to: number, prec: (e: Extension) => Extension = (e) => e) =>
+  prec(EditorView.decorations.of(Decoration.set(Decoration.mark({ class: cls }).range(from, to))));
+
+const DOC = "return request.app.state.credits";
+
+describe("selectionMarks", () => {
+  it.each([
+    ["default", (e: Extension) => e],
+    ["high (Lezer highlighter)", Prec.high],
+    ["lowest", Prec.lowest],
+  ])("paints selected text inside a %s-precedence background mark", (_, prec) => {
+    // The reporter's case: a light-scheme warning background over `request.app.state.credits`.
+    const v = view(DOC, EditorSelection.single(7, DOC.length), [
+      backgroundMark("cm-lintRange-warning", 7, DOC.length, prec),
+      selectionMarks,
+    ]);
+    const selected = [...v.contentDOM.querySelectorAll(".cm-openidea-selected")];
+    expect(selected.map((e) => e.textContent).join("")).toBe(DOC.slice(7));
+    for (const el of selected) expect(el.closest(".cm-lintRange-warning")).not.toBeNull();
+  });
+
+  it("covers every range of a multi-selection, partially overlapping marks too", () => {
+    const v = view(DOC, EditorSelection.create([EditorSelection.range(0, 3), EditorSelection.range(10, 20)], 1), [
+      backgroundMark("cm-openidea-findMatch", 15, 24),
+      selectionMarks,
+    ]);
+    const text = [...v.contentDOM.querySelectorAll(".cm-openidea-selected")].map((e) => e.textContent).join("|");
+    expect(text.replace(/\|/g, "")).toBe(DOC.slice(0, 3) + DOC.slice(10, 20));
+    const inMatch = [...v.contentDOM.querySelectorAll(".cm-openidea-findMatch .cm-openidea-selected")];
+    expect(inMatch.map((e) => e.textContent).join("")).toBe(DOC.slice(15, 20));
+  });
+
+  it("adds nothing for an empty selection and clears when the selection collapses", () => {
+    const v = view(DOC, EditorSelection.single(0, 6), [selectionMarks]);
+    expect(v.contentDOM.querySelector(".cm-openidea-selected")).not.toBeNull();
+    v.dispatch({ selection: EditorSelection.cursor(3) });
+    expect(v.contentDOM.querySelector(".cm-openidea-selected")).toBeNull();
+  });
+});
diff --git a/src/editor/core/cm/selectionMarks.ts b/src/editor/core/cm/selectionMarks.ts
new file mode 100644
index 00000000..eadee2ce
--- /dev/null
+++ b/src/editor/core/cm/selectionMarks.ts
@@ -0,0 +1,47 @@
+import { Prec, RangeSetBuilder, type Extension } from "@codemirror/state";
+import { Decoration, EditorView, ViewPlugin, type DecorationSet, type ViewUpdate } from "@codemirror/view";
+
+/**
+ * `drawSelection` paints the selection in a layer behind the text, so any mark with its own
+ * background (light-scheme warnings, find matches, usages, semantic backgrounds…) hides it.
+ * This repaints selected text in the innermost span: higher-precedence marks nest closer to the
+ * text, and the only other `Prec.highest` marks (LSP semantic tokens) set colour, not background.
+ */
+const selectedMark = Decoration.mark({ class: "cm-openidea-selected" });
+
+function selectedRanges(view: EditorView): DecorationSet {
+  const builder = new RangeSetBuilder<Decoration>();
+  const ranges = view.state.selection.ranges.filter((r) => !r.empty);
+  if (!ranges.length) return Decoration.none;
+  for (const { from: vFrom, to: vTo } of view.visibleRanges)
+    for (const r of ranges) {
+      const from = Math.max(r.from, vFrom);
+      const to = Math.min(r.to, vTo);
+      if (from < to) builder.add(from, to, selectedMark);
+    }
+  return builder.finish();
+}
+
+const plugin = ViewPlugin.fromClass(
+  class {
+    decorations: DecorationSet;
+    constructor(view: EditorView) {
+      this.decorations = selectedRanges(view);
+    }
+    update(u: ViewUpdate) {
+      if (u.selectionSet || u.docChanged || u.viewportChanged) this.decorations = selectedRanges(u.view);
+    }
+  },
+  { decorations: (p) => p.decorations },
+);
+
+const theme = EditorView.baseTheme({
+  ".cm-openidea-selected": {
+    backgroundColor: "var(--editor-selection-inactive, var(--bg-editor-selection-inactive))",
+  },
+  "&.cm-focused .cm-openidea-selected": {
+    backgroundColor: "var(--editor-selection, var(--bg-editor-selection))",
+  },
+});
+
+export const selectionMarks: Extension = [Prec.highest(plugin), theme];
diff --git a/src/features/notebook/CellEditor.tsx b/src/features/notebook/CellEditor.tsx
index 627ea58f..9089b89f 100644
--- a/src/features/notebook/CellEditor.tsx
+++ b/src/features/notebook/CellEditor.tsx
@@ -12,6 +12,7 @@ import { defaultKeymap, indentWithTab } from "@codemirror/commands";
 import { bracketMatching, indentOnInput, syntaxHighlighting } from "@codemirror/language";
 import { openideaTheme } from "@/editor/core/cm/theme";
 import { openideaHighlightStyle } from "@/editor/core/cm/highlight";
+import { selectionMarks } from "@/editor/core/cm/selectionMarks";
 import { findLanguageDescription, loadSupport } from "@/editor/core/cm/languages";
 import { tx } from "@/platform/i18n";
 import type { NotebookSession } from "./session";
@@ -43,6 +44,7 @@ export function CellEditor({
       syntaxHighlighting(openideaHighlightStyle),
       lineNumbers(),
       drawSelection(),
+      selectionMarks,
       highlightActiveLine(),
       highlightSpecialChars(),
       bracketMatching(),
diff --git a/src/features/vcs/cm.ts b/src/features/vcs/cm.ts
index 131c06af..07ae5810 100644
--- a/src/features/vcs/cm.ts
+++ b/src/features/vcs/cm.ts
@@ -270,9 +270,10 @@ export const viewerTheme = EditorView.theme(
     "&.cm-openidea-ligatures .cm-scroller": { fontVariantLigatures: "normal" },
     ".cm-content": { caretColor: "var(--caret, var(--fg-strong))", WebkitUserSelect: "text", userSelect: "text" },
     ...caretStyles,
-    "&.cm-focused > .cm-scroller > .cm-selectionLayer .cm-selectionBackground, .cm-selectionBackground, ::selection": {
-      backgroundColor: "var(--bg-selected-strong)",
-    },
+    "&.cm-focused > .cm-scroller > .cm-selectionLayer .cm-selectionBackground, .cm-selectionBackground, ::selection, .cm-openidea-selected, &.cm-focused .cm-openidea-selected":
+      {
+        backgroundColor: "var(--bg-selected-strong)",
+      },
     ".cm-activeLine": { backgroundColor: "var(--bg-current-line)" },
     ".cm-gutters": {
       backgroundColor: "var(--bg-app)",