Have you found an extension for Vivaldi browser, that’s not on the Chrome Web Store but available on the Opera add-ons site? Don’t worry! You can still able to install Opera Extensions — which have .nex as file extension – in Vivaldi, here is how.
Installing Opera Extensions in Vivaldi browser
1. Go to Opera add-ons site in Vivaldi, visit the extension page and click on ‘Add to Opera’ even though it is grayed out
2. Click on get it anyway and, click on Save As, choose the destination folder and click ‘Save’
3. Launch Windows Explorer, open Folder Options and ensure Windows shows file name extensions.
4. Now change the extension file type to crx from nex, for e.g. extensionname.nex should be changed to extensionname.crx.
5. Visit vivaldi://extensions page, drag and drop the extension, which we’ve changed to Chrome extension, it will be installed without any issues.
This way, you can able to install extensions not only from Chrome Web Store but also from the Opera add-ons site as well in Vivaldi browser.