Unfortunately, the first option ("French") is the default, which means that every textbox I go to, regardless of what I chose in the previous textbox, the spellcheck language is reset to French. Whatever the case, I want to be rid of all but "English (United States)", "Persian (Iran)", and "French (France)", in that order, with "English (United States)" as the DEFAULT. Now I don't deny that I may have gone on a splurge many years ago having discovered new languages' spellcheck.
![firefox spell checker plugin firefox spell checker plugin](https://static.helpjuice.com/helpjuice_production/uploads/upload/image/5745/direct/1591810483209-spellcheck.jpg)
The others read, in order, "French (Belgium)", "English (United Kingdom)", "French (Luxembourg)", "English (United States)", "French (Swiss)", "French (France)", "English (South Africa)", "French (Canada)", "Persian", "Persian (Iran)", "English (Australia)".
![firefox spell checker plugin firefox spell checker plugin](https://user-media-prod-cdn.itsre-sumo.mozilla.net/uploads/images/2018-09-06-00-28-41-44a50f.png)
Running Ubuntu 13.04, firefox can't help but highlight every word red every time I type into a textbox, because the top entry in RIGHTCLICK>LANGUAGES is "French".
![firefox spell checker plugin firefox spell checker plugin](https://i.stack.imgur.com/63cGt.png)
webglRenderer: NVIDIA Corporation - GeForce GTX 470/PCIe/SSE2.