Processing toolbox won't open tools

Since yesterday the processing toolbox of QGIS 3.10.9 AND 3.14.15 won’t open any tools. Originally, I wanted to use the select by location tool, but after trying no tool at all will open. It doesn’t matter if I double click on it, execute or execute as batch. I have tried uninstalling it and reinstalling it, but it still doesn’t work.

QGIS 2.14 however, does still work, but it is much slower and doesn’t have all the features I will be needing. Is there someone who had a similar problem, and can help me out?