Sleazy Fork is available in English.
Partially fade/remove non-english, HQ thumbnails, mark as read, subs, version grouping etc.
< Rückmeldungen aufNHentai Improved
Latest version appears to be working fine on Firefox v119.0 / Tampermonkey 4.19.0
Try:
Disable other extensions temporarily, to make sure there are no weird conflicts
Check console for errors (F12 > select console)
I'm just commenting to try and find why the script stopped working. Version 1.8.9 was working fine, and when it updated to 1.9, it no longer works correctly. I still see darkened non-english manga, but i cannot look for duplicates in other languages, I cannot access subscriptions to authors nor change the script settings. I haven't changed anything else in the browser. Running on latest Firefox with Tampermonkey 4.18.1.