User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.81 Safari/537.36

Steps to reproduce:

Spell check Swedish text

Actual results:

Not sure what triggered this, I assume an upgrade of Firefox. To me it seems that Firefox spell checker marks all words containing Swedish characters as incorrect: 'å', 'ä' och 'ö'.

Expected results:

Correctly spelled Swedish words with 'å', 'ä' och 'ö' should not show as incorrectly spelled.

The Bugbug bot thinks this bug should belong to the 'Core::Spelling checker' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Tried out with Firefox release 93.0 on Windows 10, x64 platform, both with Swedish Swedish language packs and Swedish set as the preferred language. On Firefox, checking spelling during typing is enabled. The Swedish language pack version is 93.0buildid20210927210923 .

With the text below copied to bugzilla comment box and to w3schools try-it-out textarea, the comment box shows squiggles while the textarea doesn't:

"För att kunna erbjuda en så bra upplevelse som möjligt använder vi och våra partners cookies och liknande tekniker som innebär att vi lagrar och får tillgång till viss information på din enhet."

In the right-click menu, "Check spelling/Kontrollera stavning" is enabled but for the former site the language option under it is set to English while for the latter it equals Swedish. Changing both to Swedish removes the unexpected squiggles.

Both sites have lang attribute set to en and en-US.

Can the issue be alleviated by changing the language from the right-click menu "Languages"?

(In reply to Jari Jalkanen from comment #3)

Can the issue be alleviated by changing the language from the right-click menu "Languages"?

Might be something with my computer but I keep getting the issue. Tested right now both in Wordpress and writing an email.
See 'spellcheck_swedish.jpg'. All the words containing 'å'. 'ä' or 'ö' shows as misspelled even if they are correctly spelled.

Not the biggest issue in the world but very annoying when spellchecking a Swedish text.

Does the issue go away if, following "Add dictionaries" of https://support.mozilla.org/en-US/kb/how-do-i-use-firefox-spell-checker#w_switching-dictionaries, the Swedish dictionary is first removed, and then added again?

(In reply to Jari Jalkanen from comment #6)

Does the issue go away if, following "Add dictionaries" of https://support.mozilla.org/en-US/kb/how-do-i-use-firefox-spell-checker#w_switching-dictionaries, the Swedish dictionary is first removed, and then added again?

Bug 1748408 is caused by a regression that landed in Firefox 96, reporter mentions Firefox 93, so it seems unlikely that's the same issue?

For what it's worth, the dictionary on AMO hasn't been updated since April 2020, the one included in the build it's way older than that (2011)
https://addons.mozilla.org/firefox/addon/g%C3%B6rans-hemmasnickrade-ordli/versions/

It must be something else then.

I can't reproduce this either.