Just wanted to note, had trouble connecting kbonk to OBS and it took me a bit to figure out why. I had saved the file to a folder that required admin rights to edit or change and I don't have admin rights (idk why, it's my laptop and I'm the only user, but that's a separate issue), so I think OBS was unable to access that file because of it.
In short, if someone is having an issue connecting the app to OBS via the local file html folder, ensure they have admin access or it's in a folder that does not require admin access.
Hope this helps :)