Override not working

All cache is off but whenever I upload an override.css file it is just blank... Even if I edit the file in the backend through template manager when I save it it saves nothing. Also how to add a custom javascript file??

Hi,
I saw this issue only ones,
it was server settings - security level was too high.
All I can suggest to update that file via FTP tool. Sorry, but ... it's not our fault.
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I guess, you cannot edit online not only that file but all others.

All other files are editable and working fine. I've updated the footer and head layout files and edited other css files in the css folder but obviously I would like to transfer those changes all into the custom css file. There is no permission problems on the server and security level is normal. I have tried deleting the file from the server and uploading via ftp but this doesn't help. The issue occurs on front end page refresh, the file is just set back to blank with no content. Like it's being overwritten by the template cache.

It is something to do with recompiling LESS. If this option is off the override.css doesn't get wiped.

Good to know.
You can also in case of emergency.... use addcional css file loaded by plugin, not template.