custom hints CSS not activating upon update, works after browser restart

[parogen]

With the 'Auto switch between light and dark mode' setting off, I expect the link hints CSS to activate.

Since an update, hints are using default CSS, but when I go to the setting and toggle the setting back to off (originally off -> on -> partial -> off), the custom CSS is turned on for the vimium options page. However, once the options page refreshes or going to any other webpage, hints are all using default CSS.

Seems to be that on browser restart, it applies.

On Windows 10, Firefox