Ive trying everything . I tried unpacking and then installing .. Nothing works .. This a serious issue ....
A browser without add ons?
same as here #923 i already opened an issue but someone closed it .. this is a very serious bug .
I tried unpacking and then installing
Can you describe step-by-step how you tried to unpack and install extensions? A video works too.
Have you tried to right-click *.crx and 'open it with" → "Chromium" like @perfect7gentleman suggested in a closed bug?
I just did and it worked flawlessly.
Ah nevermind. I didn't notice, that it didn't work for you.
Anyway for such a weird case we need more information from you. Help us help you!
Plainly stating that it doesn't work does not help at all.
Second this problem. Tried enabling Developer mode in chrome://extensions/, drag and drop an extension from Windows Explorer and the whole page freezes at Drop to Install.
Right clicking *.crx and open it with Ungoogled Chromium doesn't work as well. It gets stick on "Adding to Chromium..."
Here's a screenshot showing both problems. It happens with every extension. Windows 10 1909 x64 and Ungoogled Chromium 80.0.3987.132 x64
How can I log further this issue?

love you for this .
Ok, I unpacked the extension — uncompress the crx file into a folder — then I loaded as unpacked and it worked.
Anyways, I installed the extension Chromium Web Store using this method but I'm still unable to install extensions from the Chrome Web Store or anywhere as long as it download/uses a *crx file. It gets stuck on "Adding to Chromium..." forever. I have to unpack every single extension to get it working.
Would be great if this problem get fixed!
I don't get it, man. Why do you need UGC in Windows 10?
Closing as a duplicate of #923 and https://github.com/ungoogled-software/ungoogled-chromium-windows/issues/23.
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I don't get it, man. Why do you need UGC in Windows 10?