This is basically a backport of PR #3780 and PR #3799, as well as the recently accepted and merged Japanese and Polish translations, which unfortunately didn't make it into that cleanup. For a detailed list of changes, please refer to the linked pull requests.
Of course, due to some differences between JEI for 1.21.1 and 1.20.1, not everything could be backported, and even if it could, it didn't always make sense. For example, almost every time I switched to an older version, there were some differences in the configuration options offered by JEI. So, for obvious reasons, there was no point in backporting descriptions for options that simply don't exist in that older version.
In addition, there's also something new here — the removal of all remnants of the old in-game configuration interface from translation files. This interface hasn't been in use for years, the configuration option descriptions are outdated, and some of them don't even correspond to any available options in config files anymore, while others are just missing. If the in-game configuration interface were to be reintroduced in JEI for this Minecraft version, it would probably make more sense to backport everything from 1.21.1 instead.
This is basically a backport of PR #3780 and PR #3799, as well as the recently accepted and merged Japanese and Polish translations, which unfortunately didn't make it into that cleanup. For a detailed list of changes, please refer to the linked pull requests.
Of course, due to some differences between JEI for 1.21.1 and 1.20.1, not everything could be backported, and even if it could, it didn't always make sense. For example, almost every time I switched to an older version, there were some differences in the configuration options offered by JEI. So, for obvious reasons, there was no point in backporting descriptions for options that simply don't exist in that older version.
In addition, there's also something new here — the removal of all remnants of the old in-game configuration interface from translation files. This interface hasn't been in use for years, the configuration option descriptions are outdated, and some of them don't even correspond to any available options in config files anymore, while others are just missing. If the in-game configuration interface were to be reintroduced in JEI for this Minecraft version, it would probably make more sense to backport everything from 1.21.1 instead.