Forward port of 6.x changelog to main branch (#1429)

Author: ianthomas23

CHANGELOG.md

@@ -128,30 +128,73 @@ Note the changelog here is not correct, presumably due to the recent branch rena
 
 <!-- <END NEW CHANGELOG ENTRY> -->
 
-## 6.30.0a0
+## 6.30.1
 
-Pre-release to allow further testing of subshell implementation.
+This is a bugfix release to fix a significant bug introduced in 6.30.0 that allowed control messages to be handled concurrently rather than sequentially which broke debugging in JupyterLab and VSCode.
 
-([Full Changelog](https://github.com/ipython/ipykernel/compare/v6.29.5...5d90d9e10425886deb4b0f1676b14b1701522b3c))
+([Full Changelog](https://github.com/ipython/ipykernel/compare/v6.30.0...357c908eab4ae97bb17c5dcabc7ee981df8ecb29))
+
+### Bugs fixed
+
+- Correct use of asyncio.Lock to process a single control message at a time [#1416](https://github.com/ipython/ipykernel/pull/1416) ([@ianthomas23](https://github.com/ianthomas23))
+
+### Maintenance and upkeep improvements
+
+- Backport: Remove links in changelog to github milestones that no longer exist [#1417](https://github.com/ipython/ipykernel/pull/1417) ([@ianthomas23](https://github.com/ianthomas23))
+
+### Contributors to this release
+
+([GitHub contributors page for this release](https://github.com/ipython/ipykernel/graphs/contributors?from=2025-07-21&to=2025-08-04&type=c))
+
+[@ianthomas23](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aianthomas23+updated%3A2025-07-21..2025-08-04&type=Issues)
+
+## 6.30.0
+
+This release fixes three bugs but is primarily a maintenance release bringing support for Python 3.13 and updating dependencies. It does not include subshells which will be in the upcoming 7.0.0 release. Users and downstream libraries that wish to avoid subshells should pin to `ipykernel < 7`.
+
+([Full Changelog](https://github.com/ipython/ipykernel/compare/b1283b144...d9bd546a4dc49a41c3ad5fcc5d4a61f259973182))
 
 ### Enhancements made
 
-- Subshells implemented using tornado event loops on 6.x branch [#1396](https://github.com/ipython/ipykernel/pull/1396) ([@ianthomas23](https://github.com/ianthomas23))
+- Remove control queue [#1210](https://github.com/ipython/ipykernel/pull/1210) ([@ianthomas23](https://github.com/ianthomas23))
 
 ### Bugs fixed
 
-- [Bugfix] Set shell idle when message skipped by "should_handle" in "dispatch_shell" [#1395](https://github.com/ipython/ipykernel/pull/1395) ([@dby-tmwctw](https://github.com/dby-tmwctw))
+- Set shell idle when message skipped by "should_handle" in "dispatch_shell" [#1395](https://github.com/ipython/ipykernel/pull/1395) ([@dby-tmwctw](https://github.com/dby-tmwctw))
+- Fixed error accessing sys.stdout/sys.stderr when those are None [#1247](https://github.com/ipython/ipykernel/pull/1247) ([@gregory-shklover](https://github.com/gregory-shklover))
+- Allow datetime or str in test_sequential_control_messages [#1219](https://github.com/ipython/ipykernel/pull/1219) ([@ianthomas23](https://github.com/ianthomas23))
 
 ### Maintenance and upkeep improvements
 
+- 6.x backports [#1406](https://github.com/ipython/ipykernel/pull/1406) ([@ianthomas23](https://github.com/ianthomas23))
+- Update pre-commit and github actions [#1401](https://github.com/ipython/ipykernel/pull/1401) ([@ianthomas23](https://github.com/ianthomas23))
+- Test more python versions on 6.x branch [#1398](https://github.com/ipython/ipykernel/pull/1398) ([@davidbrochart](https://github.com/davidbrochart))
 - Backports and extra changes to fix CI on 6.x branch [#1390](https://github.com/ipython/ipykernel/pull/1390) ([@ianthomas23](https://github.com/ianthomas23))
+- Remove nose import. [#1368](https://github.com/ipython/ipykernel/pull/1368) ([@Carreau](https://github.com/Carreau))
+- Test more python versions [#1358](https://github.com/ipython/ipykernel/pull/1358) ([@davidbrochart](https://github.com/davidbrochart))
+- Fix expected text depending on IPython version. [#1354](https://github.com/ipython/ipykernel/pull/1354) ([@Carreau](https://github.com/Carreau))
+- Licence :: * trove classifiers are deprecated [#1348](https://github.com/ipython/ipykernel/pull/1348) ([@Carreau](https://github.com/Carreau))
+- Try to fix spyder kernel install [#1337](https://github.com/ipython/ipykernel/pull/1337) ([@Carreau](https://github.com/Carreau))
+- Remove test_check job [#1335](https://github.com/ipython/ipykernel/pull/1335) ([@Carreau](https://github.com/Carreau))
+- Don't rerun test with --lf it hides failures. [#1324](https://github.com/ipython/ipykernel/pull/1324) ([@Carreau](https://github.com/Carreau))
+- Remove link to numfocus for funding. [#1320](https://github.com/ipython/ipykernel/pull/1320) ([@Carreau](https://github.com/Carreau))
+- Remove downstream_check [#1318](https://github.com/ipython/ipykernel/pull/1318) ([@Carreau](https://github.com/Carreau))
+- Copy payloadpage.page from IPython [#1317](https://github.com/ipython/ipykernel/pull/1317) ([@Carreau](https://github.com/Carreau))
+- Remove base setup [#1299](https://github.com/ipython/ipykernel/pull/1299) ([@davidbrochart](https://github.com/davidbrochart))
+- Rely on intrsphinx_registry to keep intersphinx up to date. [#1290](https://github.com/ipython/ipykernel/pull/1290) ([@Carreau](https://github.com/Carreau))
+- Drop support for Python 3.8 [#1284](https://github.com/ipython/ipykernel/pull/1284) ([@ianthomas23](https://github.com/ianthomas23))
+- Start testing on 3.13 [#1277](https://github.com/ipython/ipykernel/pull/1277) ([@Carreau](https://github.com/Carreau))
+- Build docs on ubuntu [#1257](https://github.com/ipython/ipykernel/pull/1257) ([@blink1073](https://github.com/blink1073))
 - Avoid a DeprecationWarning on Python 3.13+ [#1248](https://github.com/ipython/ipykernel/pull/1248) ([@hroncok](https://github.com/hroncok))
+- Catch IPython 8.24 DeprecationWarnings [#1242](https://github.com/ipython/ipykernel/pull/1242) ([@s-t-e-v-e-n-k](https://github.com/s-t-e-v-e-n-k))
+- Add compat with pytest 8 [#1231](https://github.com/ipython/ipykernel/pull/1231) ([@blink1073](https://github.com/blink1073))
+- Set all min deps [#1229](https://github.com/ipython/ipykernel/pull/1229) ([@blink1073](https://github.com/blink1073))
 
 ### Contributors to this release
 
-([GitHub contributors page for this release](https://github.com/ipython/ipykernel/graphs/contributors?from=2024-07-01&to=2025-06-05&type=c))
+([GitHub contributors page for this release](https://github.com/ipython/ipykernel/graphs/contributors?from=2024-07-01&to=2025-07-21&type=c))
 
-[@Carreau](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3ACarreau+updated%3A2024-07-01..2025-06-05&type=Issues) | [@ccordoba12](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Accordoba12+updated%3A2024-07-01..2025-06-05&type=Issues) | [@davidbrochart](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Adavidbrochart+updated%3A2024-07-01..2025-06-05&type=Issues) | [@dby-tmwctw](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Adby-tmwctw+updated%3A2024-07-01..2025-06-05&type=Issues) | [@ianthomas23](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aianthomas23+updated%3A2024-07-01..2025-06-05&type=Issues) | [@ivanov](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aivanov+updated%3A2024-07-01..2025-06-05&type=Issues) | [@jasongrout](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Ajasongrout+updated%3A2024-07-01..2025-06-05&type=Issues) | [@krassowski](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Akrassowski+updated%3A2024-07-01..2025-06-05&type=Issues) | [@meeseeksmachine](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Ameeseeksmachine+updated%3A2024-07-01..2025-06-05&type=Issues) | [@minrk](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aminrk+updated%3A2024-07-01..2025-06-05&type=Issues)
+[@Carreau](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3ACarreau+updated%3A2024-07-01..2025-07-21&type=Issues) | [@ccordoba12](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Accordoba12+updated%3A2024-07-01..2025-07-21&type=Issues) | [@davidbrochart](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Adavidbrochart+updated%3A2024-07-01..2025-07-21&type=Issues) | [@dby-tmwctw](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Adby-tmwctw+updated%3A2024-07-01..2025-07-21&type=Issues) | [@gregory-shklover](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Agregory-shklover+updated%3A2024-07-01..2025-07-21&type=Issues) | [@ianthomas23](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aianthomas23+updated%3A2024-07-01..2025-07-21&type=Issues) | [@ivanov](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aivanov+updated%3A2024-07-01..2025-07-21&type=Issues) | [@jasongrout](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Ajasongrout+updated%3A2024-07-01..2025-07-21&type=Issues) | [@krassowski](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Akrassowski+updated%3A2024-07-01..2025-07-21&type=Issues) | [@meeseeksmachine](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Ameeseeksmachine+updated%3A2024-07-01..2025-07-21&type=Issues) | [@minrk](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Aminrk+updated%3A2024-07-01..2025-07-21&type=Issues) | [@nathanmcavoy](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3Anathanmcavoy+updated%3A2024-07-01..2025-07-21&type=Issues) | [@s-t-e-v-e-n-k](https://github.com/search?q=repo%3Aipython%2Fipykernel+involves%3As-t-e-v-e-n-k+updated%3A2024-07-01..2025-07-21&type=Issues)
 
 ## 6.29.5