Libre Writer spell check not working
Spell check is an important part of any modern text processor. We need to ensure it is is working correctly. This is a common error on Libre Office that can be easily rectified.
Tools > Options > Language Settings > General > Default languages for Documents > Western
For English, only five English locales are supported for spellcheck here, you need to ensure that one of these is set up for your system for spellcheck to work.