Unable to use any application or return to homescreen after opening application menu

[Prachi]

OS- Ubuntu 20.04
Comfortably using since 25 April 2020

The issue started yesterday.
After clicking the show application button on the taskbar, there is no way to return back to the home screen again. There is an extra black box available in the right corner. I am able to open the application but not use them.
On opening any of my favorite applications from the taskbar that application freezes and a red circle with white cross appear to kill this program. No even the close, or minimize commands word expect that big cross on the left top. This is sometimes sorted by restarting but sometimes even that doesn't help.
Please help me sort this issue. Its urgent.

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1891429/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Daniel van Vugt (vanvugt)]

Thanks for the bug report. Please tell us if the problem is still occurring and if so then run this command to collect more system info:

  apport-collect 1891429

[Launchpad Janitor (janitor)]

[Expired for gnome-shell (Ubuntu) because there has been no activity for 60 days.]