How to fix all applications missing in Ubuntu's dash?

having an issue with the dashboard where applications don't show app in the applications lense or when searched. Tried everything in these topics:

Applications not showing in Unity Dash

Dash (from Unity) does not showing Applications

But nothing has worked so far. Would really wat to avoid reinstalling everything since i use Vivaldi and there is no where to export my stuff from it. Using 16.04

Edit: All apps aren't being displayed, only show files and web results. Checked the filters: applications is enabled

Edit 2: after a reboot got a crash report, might be related since the culprit of the crash was unity-lens-loader. Will try to purge and see what happens.
Could not purge it, unity-lens-loader is not a package, it's a executable created by libunity9, should I purge and reinstall it?

Solution 1:

The problem seems to have been fixed; the apps are showing up again. I am not sure what fixed it, but here are all the things I did before the next reboot:

I renamed unity-scope-loader to unity-scope-loader.bak in /usr/bin. I
tried to reinstall libunity9 though it always gave me an error that it couldn't overwrite unity-scope-loader. Finally, I ran sudo dpkg-reconfigure libunity9.