**Backport:** https://codeberg.org/forgejo/forgejo/pulls/4452
## Regexp fixes
This fixes#4431 by adjusting the related regular expressions. Also it allows to have multiple spaces between `-` or `*` and the following brackets.
Related is the following gitea PR: https://github.com/go-gitea/gitea/pull/3296. I wonder a bit why the author stated
> Also fixed the requirement for one character after the blank of - [ ] .
I don't see a reason why
```
- [x]
some task
```
shall not be a valid checkbox without any character after the `]`. E.g., this would render to
- [x]
some task
The third commit fixes this issue.
### Comments
- I wonder a bit why the regexp is written in such complicated way and if
```diff
- (^\s*[-*]\s*\[[\sxX]\])|(
\s*[-*]\s*\[[\sxX]\])
+ (^|
)\s*[-*]\s*\[[\sxX]\]
```
would work the same way. Edit: I tried and indeed the second regex works as expected.
- ~~Why it is actually matching the `\s` and not just the space (` `)? (but OK, no big issue)~~ Edit: `[\t]` is also allowed. Keep it!
- Check boxes in code blocks are counted as well, but I think that this is an edge case which is not a big issue as well.
### Before
![before](https://codeberg.org/attachments/cb4f879d-cdd2-4814-aed2-5de8b5437fb2)
### After
![after](https://codeberg.org/attachments/5d54648f-dd73-4577-9a80-729016219093)
## Javascript fixes
Additionally, while testing I figured out, that currently checkboxes with capital `X` like
```
- [X] another task
```
- [X] another task
cannot be unchecked. Thus, the second commit fixes that issue as well.
## Checklist
The [developer guide](https://forgejo.org/docs/next/developer/) contains information that will be helpful to first time contributors. There also are a few [conditions for merging Pull Requests in Forgejo repositories](https://codeberg.org/forgejo/governance/src/branch/main/PullRequestsAgreement.md). You are also welcome to join the [Forgejo development chatroom](https://matrix.to/#/#forgejo-development:matrix.org).
### Tests
- I added test coverage for Go changes...
- [ ] in their respective `*_test.go` for unit tests.
- [x] in the `tests/integration` directory if it involves interactions with a live Forgejo server.
- I added test coverage for JavaScript changes...
- [ ] in `web_src/js/*.test.js` if it can be unit tested.
- [ ] in `tests/e2e/*.test.e2e.js` if it requires interactions with a live Forgejo server (see also the [developer guide for JavaScript testing](https://codeberg.org/forgejo/forgejo/src/branch/forgejo/tests/e2e/README.md#end-to-end-tests)).
### Documentation
- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [x] I did not document these changes and I do not expect someone else to do it.
### Release notes
- [ ] I do not want this change to show in the release notes.
- [x] I want the title to show in the release notes with a link to this pull request.
- [ ] I want the content of the `release-notes/<pull request number>.md` to be be used for the release notes instead of the title.
Co-authored-by: Robert Wolff <mahlzahn@posteo.de>
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/4735
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: forgejo-backport-action <forgejo-backport-action@noreply.codeberg.org>
Co-committed-by: forgejo-backport-action <forgejo-backport-action@noreply.codeberg.org>