To be fair, the change is reasonably simple and persists across upgrades.
Here are the instructions I followed to take twoot.space up to 5K characters:
https://fouquet.me/2023/09/22/mastodon-char-limit
(However, I much prefer the configurable character count of GoToSocial. There's no post editing on that yet, although it's on the outstanding milestones list.)
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