macOS Catalina beachball appears when I use TextEdit or Preview apps

I have a MacBook with macOS Catalina 10.15.3 installed.

I'm now noticing that whenever I open an image file with the Preview app, a beachball appears right about when I quit the app.

Also, a beachball appears whenever I open a text file using the TextEdit app.

Is there any way I can reset things to fix these problems?

Hi I did some more Google searching, and so the answer for this bug I was facing is to Disable the "Dropbox Finder Extensions" in the "Extensions" section in System Preference.

It seems the Finder features of Dropbox (like green dot next to filename in finder etc.) was causing beachballs in using TextEdit & Preview. Now it's been fixed for me.

Since it's a bug, I hope Dropbox & Apple will fix it.