Greasy Fork is available in English.
Adds: sidebar toggle bar (click on blue vertical separator bar), auto collapsing sticky floating table of contents at top left (hover mouse on it to expand), collapsible sections (click section title to toggle), section links (for getting URL to page sections), auto popup sticky table headers (when table height is longer than the screen), table manipulations (double click empty space of a table cell to show menu).
Great script! Works really well. But, on my setup, the floating table header doesn't match the table width and then the headers get completely misaligned. If I disable a single CSS padding rule though it almost matches exactly. See the screen captures. Specifically, it's this rule created by
https://en.wikipedia.org/w/load.php:I'm on Intel macOS 10.13.6 High Sierra, Mozilla Firefox 80.0.1 - Build ID 20200831163820 No other userscripts or extensions running/modifying Wikipedia page