Dashboard doesn't load properly in Firefox (PC) anymore

WaniKani Bugs & Errors
1

I use Firefox on my PC as my primary browser for WaniKani and other japanese language extensions. About a week ago a problem started where the page loads but not the interface data or buttons.

I’ve contacted WaniKani support but haven’t heard from them after they asked me for browser version and OS.

Would anybody else have experienced something similar and were able to fix it?

  • Firefox v151.0.1
  • I’ve cleared WaniKani cache and cookies
  • Disabled VPN and uBlock origin extension
  • Chrome and Firefox on my phone work fine; Chrome on my PC works fine

2026-05-19 10_1740-WaniKani Dashboard — Mozilla Firefox
2026-05-19 10_1740-WaniKani Dashboard — Mozilla Firefox1431×815 40 KB

SOLUTION: Creating a new Firefox profile fixed the problem. Somehow clearing cache and cookies just for WaniKani in the old profile wasn’t enough.

If it’s not too much trouble you can simply create a new profile but I wanted to keep my other cookies, extensions, and open tabs so I took these steps:

  1. Open about:profiles and find the directory for your broken profile, keep that folder open
  2. In Firefox create a new Firefox profile
  3. Close Firefox
  4. Restore open tabs to new profile copy “sessionstore.jsonlz4” file and “sessionstore-backups” folder to the new profile folder
  5. Restore cookies to new profile copy “cookies.sqlite” and “key4.db” files to new profile folder
  6. Restore extensions to new profile copy “extensions” folder and “extensions.json” file to new profile folder
  7. Restart Firefox
2

I use the same Firefox version and got no issues.

3

Thanks, I was able to fix it with a new profile in Firefox, something went wrong that clearing site cache and cookies didn’t even work. I’m updating my post with the steps I did.