This is a support thread for add-on Custom Debug Info.
Custom Debug Info - for Development (Created by Shige)1616945135This add-on is for add-on developers not for general learners. It displays debug info directly and makes errors easier to read. (It does nothing unless an error occurs.)
For more detailed how to use it please read the wiki.
Would this also show an error that is made inside the card template while trying out javascript codes
Probably not, this add-on is customizing Anki’s default error popup so it will not display anything that does not display errors by default.
I think advanced editing is generally using a code editor. e.g. this extension can be used to edit Anki card templates in VSCode (code editor).
But tools like VScode are for programmers and are complicated to set up. If you want to edit easily you may want to use a web tool like Codepen.
It can be embedded like this (Embed → Iframe → Copy Code):
Wiki: Custom Debug Info 