RangeError: Invalid line number 24 in 23-line document

[ops-handler]

Error

Invalid line number 24 in 23-line document

Stack trace

../app/javascript/components/bootcamp/CSSExercisePage/SimpleCodeMirror/SimpleCodeMirror.tsx:18 in SimpleCodeMirror
../app/javascript/components/bootcamp/CSSExercisePage/LHS/CSSEditor.tsx:20 in CSSEditor
div
../app/javascript/components/bootcamp/CSSExercisePage/LHS/LHS.tsx:7 in LHS
div
div
../app/javascript/components/bootcamp/CSSExercisePage/CSSExercisePage.tsx:19 in CSSExercisePage
Suspense
../node_modules/@sentry/react/src/errorboundary.tsx:101 in new ErrorBoundary
../node_modules/@tanstack/react-query/src/QueryClientProvider.tsx:30 in QueryClientProvider

Tracking Details

• Project: exercism-js
• Sentry: RangeError: Invalid line number 24 in 23-line document
• Culprit: lockedLineGutterHighlighter(app/javascript/components/bootcamp/JikiscriptExercisePage/CodeMirror/extensions/read-only-ranges/readOnlyLineDeco)
• First seen: Apr 25, 2026