Affected versions

Firefox 100.0a1
Firefox 99.0b8
Firefox 98.0.2

Affected platforms

Windows 10 x64
macOS 11.6
Ubuntu 20.04 x64

Steps to reproduce

1. Open Firefox.
2. Make sure to have a couple of dictionaries added (e.x English and Romanian).
3. Go to http://onlinetexteditor.com/
4. Make sure both languages are selected (e.x English and Romanian).
5. Introduce a misspelled text in Romanian (e.x Cuvointe scrisse grresit).
6. Right click on the first letter (Cuovinte).
7. Observe first suggestion.

Expected result

Order the results by how close the suggested fix is to the misspelled word.

Actual Result

First suggestion is in English even if the word is written in Romanian.

This matches the behaviour in Chromium, where suggestions appear to be listed in order of installed languages as well. I'm not sure whether it is more usable to group suggestions by dictionary or sort them based upon edit distance to the misspelled word. I'd suggest we consider this issue as an potential enhancement. I'm going to mark it as blocking Bug 69687 for now, as something to revisit when thinking about the design for multiple language support.

I discussed this with Asa, and he would prefer to keep suggestions sorted by language rather than switch to sorting by edit distance. There is a problem where too many results from one language might mean we don't see a result from another language. We have Bug 1763123 to fix that.