([Full Changelog](https://github.com/jupyterlab/jupyterlab/compare/jupyterlab/example-services-outputarea3.1.9...2444ed0588adba1999a5575304d452a3b512c913))
Enhancements made
- Add a menu entry to show/hide hidden files in the filebrowser [11206](https://github.com/jupyterlab/jupyterlab/pull/11206) ([loichuder](https://github.com/loichuder)) - activation instructions: [see documentation](https://jupyterlab.readthedocs.io/en/latest/user/files.html#displaying-hidden-files)
- Restore Copy shareable link use of `shareUrl` [11188](https://github.com/jupyterlab/jupyterlab/pull/11188) ([fcollonval](https://github.com/fcollonval))
- Add Galata in JupyterLab [11179](https://github.com/jupyterlab/jupyterlab/pull/11179) ([fcollonval](https://github.com/fcollonval))
- Responsive Toolbar [11178](https://github.com/jupyterlab/jupyterlab/pull/11178) ([3coins](https://github.com/3coins))
- Make check margin between last modified timestamps on disk and client configurable [11153](https://github.com/jupyterlab/jupyterlab/pull/11153) ([ph-ph](https://github.com/ph-ph))
- Reuse cell id of cut cell on cut + paste [11138](https://github.com/jupyterlab/jupyterlab/pull/11138) ([smacke](https://github.com/smacke))
- Add Side-by-side Rendering [11143](https://github.com/jupyterlab/jupyterlab/pull/11143) ([blink1073](https://github.com/blink1073))
- Add show trailing whitespace option to Notebook and Text Editor [11131](https://github.com/jupyterlab/jupyterlab/pull/11131) ([blink1073](https://github.com/blink1073))
- Implement Restart and debug [11129](https://github.com/jupyterlab/jupyterlab/pull/11129) ([blink1073](https://github.com/blink1073))
- Add `preferred-dir` handling [10667](https://github.com/jupyterlab/jupyterlab/pull/10667) ([goanpeca](https://github.com/goanpeca))
- Enable disabling document-wide history tracking [10949](https://github.com/jupyterlab/jupyterlab/pull/10949) ([echarles](https://github.com/echarles))
- Removed debug switch [11185](https://github.com/jupyterlab/jupyterlab/pull/11185) ([3coins](https://github.com/3coins))
Bugs fixed
- Normalize cell source `\r` line endings [11271](https://github.com/jupyterlab/jupyterlab/pull/11271) ([jasongrout](https://github.com/jasongrout))
- Fix Webpack crypto handling [11249](https://github.com/jupyterlab/jupyterlab/pull/11249) ([blink1073](https://github.com/blink1073))
- Use standard hash type in webpack build [11234](https://github.com/jupyterlab/jupyterlab/pull/11234) ([blink1073](https://github.com/blink1073))
- Remove format from fetching options if null [11229](https://github.com/jupyterlab/jupyterlab/pull/11229) ([loichuder](https://github.com/loichuder))
- Do not continuously `cd('/')` when already in `/` [11219](https://github.com/jupyterlab/jupyterlab/pull/11219) ([minrk](https://github.com/minrk))
- Properly reset layout when toggling simple mode. [11203](https://github.com/jupyterlab/jupyterlab/pull/11203) ([jasongrout](https://github.com/jasongrout))
- Fix renaming issue in collaborative mode [11197](https://github.com/jupyterlab/jupyterlab/pull/11197) ([dmonad](https://github.com/dmonad))
- Restore workspace and open tree path [11176](https://github.com/jupyterlab/jupyterlab/pull/11176) ([blink1073](https://github.com/blink1073))
- Share notebook's metadata [11064](https://github.com/jupyterlab/jupyterlab/pull/11064) ([hbcarlos](https://github.com/hbcarlos))
- Normalize notebook cell line endings to `\n` [11141](https://github.com/jupyterlab/jupyterlab/pull/11141) ([jasongrout](https://github.com/jasongrout))
- Fix auto close brackets for console [11137](https://github.com/jupyterlab/jupyterlab/pull/11137) ([ohrely](https://github.com/ohrely))
- Add a guard to avoid kernel deadlock on multiple input request [10792](https://github.com/jupyterlab/jupyterlab/pull/10792) ([echarles](https://github.com/echarles))
Maintenance and upkeep improvements
- Extension upgrade script: Avoid throwing exceptions for certain package.json files [11278](https://github.com/jupyterlab/jupyterlab/pull/11278) ([ammgws](https://github.com/ammgws))
- Run Linter [11238](https://github.com/jupyterlab/jupyterlab/pull/11238) ([blink1073](https://github.com/blink1073))
- Fix Release Check [11218](https://github.com/jupyterlab/jupyterlab/pull/11218) ([fcollonval](https://github.com/fcollonval))
- Handle case when JupyterHub returns 424 for not running server [11205](https://github.com/jupyterlab/jupyterlab/pull/11205) ([yuvipanda](https://github.com/yuvipanda))
- Check `i18n` will pass on zeroed patch pre-release version [11214](https://github.com/jupyterlab/jupyterlab/pull/11214) ([fcollonval](https://github.com/fcollonval))
- Refactor `window.open` to make it work also in desktop app [11202](https://github.com/jupyterlab/jupyterlab/pull/11202) ([mbektas](https://github.com/mbektas))
- Rename "JupyterLab Theme" to "Theme" [11198](https://github.com/jupyterlab/jupyterlab/pull/11198) ([jtpio](https://github.com/jtpio))
- Use only context and id to check i18n [11190](https://github.com/jupyterlab/jupyterlab/pull/11190) ([fcollonval](https://github.com/fcollonval))
- Fix the "Edit on GitHub" link [11149](https://github.com/jupyterlab/jupyterlab/pull/11149) ([krassowski](https://github.com/krassowski))
- Clean up notebook test utils [11133](https://github.com/jupyterlab/jupyterlab/pull/11133) ([blink1073](https://github.com/blink1073))
- Change "Export Notebook As" to "Save and Export Notebook As" [11132](https://github.com/jupyterlab/jupyterlab/pull/11132) ([blink1073](https://github.com/blink1073))
- Make Test Server Configurable [11015](https://github.com/jupyterlab/jupyterlab/pull/11015) ([fcollonval](https://github.com/fcollonval))
- Use disableDocumentWideUndoRedo instead of enableDocumentWideUndoRedo [11215](https://github.com/jupyterlab/jupyterlab/pull/11215) ([echarles](https://github.com/echarles))
- Fix kernelspec logo handling (11175) [11183](https://github.com/jupyterlab/jupyterlab/pull/11183) ([jtpio](https://github.com/jtpio))
Documentation improvements
- Fix typo in docs: `page_config.json` [11152](https://github.com/jupyterlab/jupyterlab/pull/11152) ([achimgaedke](https://github.com/achimgaedke))
- Add a menu entry to show/hide hidden files in the filebrowser [11206](https://github.com/jupyterlab/jupyterlab/pull/11206) ([loichuder](https://github.com/loichuder))
- Fix the "Edit on GitHub" link [11149](https://github.com/jupyterlab/jupyterlab/pull/11149) ([krassowski](https://github.com/krassowski))
- Clarify sidebar switching settings [11270](https://github.com/jupyterlab/jupyterlab/pull/11270) ([joelostblom](https://github.com/joelostblom))
Contributors to this release
([GitHub contributors page for this release](https://github.com/jupyterlab/jupyterlab/graphs/contributors?from=2021-09-01&to=2021-10-14&type=c))
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