Current IDE version: 1.8.9
Current additional urls for boards/libraries.
Libraries/boards affected: all.
Issue: I get the "downloading library" message, but it stops there. Progress bar doesn't move further.
After that, Cancel, close or buttons doesn't work. I have to close Java from task manager.
I delete the files on %Appdata%/Local/Arduino15, and the generated .zip in /staging/libraries with 0KB size. I repeat the process to download, but get the same problem.
Tried uninstalling and re-installing again.
In preferences, proxy was set to auto (I don't have one), changed to no proxy and tried again. No changes.
Seems to be related to this issue: link