This is a hotfix for a few important issues that have come to light with the 4.2.11 release.
For the Classic release, you should be offered the update automatically within the next week or so. You can get the update sooner by going to ⚙ Settings → Updates → Check Now. You can also download and install it directly from the website.
Changes since 4.2.11:
- Fixed an error that was preventing some old PDN images from loading (reported here: https://forums.getpaint.net/topic/116501-error-opening-older-pdn-files/)
- Fixed a crash in the new selection outline renderer (due to misaligned Push/PopAxisAlignedClip calls)
- Changed saving to use the ReplaceFile Win32 API, which improves its compatibility
- Fixed an EndOfStreamException error that prevented some JPEGs from opening (thanks @null54 for the fix!)