1. * * Numbered list item Ook staat onder ieder woord een rode lijn en dat is zeer vervelend.

Hello truusenjanaarle,

Firefox is a browser and doesn't "do" email ....

You should contact your email provider (or their support forum), but in case you're using Thunderbird, you can post your question on the Thunderbird support forum.

See this article (in Dutch) :

https://support.mozilla.org/nl/kb/problemen-met-e-mail-en-daarbij-hulp-vinden

Do you have a dictionary installed and selected?

You can see which dictionary is selected if you right-click in a text area and open the Languages sub menu. At least one dictionary should be installed and have a check mark to indicate that it is selected.

• open the "Add Dictionaries" link to install a dictionary if you do not have one.

The spelling checker is enabled if [X] "Check Spelling" in the right-click context menu has a checkmark.

You can enable or disable spell checking globally:

• Options/Preferences -> General: Language and Appearance: "Check your spelling as you type"

You can look here for dictionaries:

• https://addons.mozilla.org/firefox/language-tools/

Note that for spell check you need a dictionary. A language pack provides string translations for the user interface.

• https://support.mozilla.org/en-US/kb/use-firefox-interface-other-languages-language-pack

You can check on the about:config page that layout.spellcheckDefault is set to 1 (multi-line) or 2 (single-line).