Safari Will Not Open Because of Nonexistent Update

I've been having an issue the last few weeks with a supposed Safari update. When Safari is open, if I click a link in a different application or a different application tries to take me to Safari (to log in, for instance), it throws an error (screenshot below) that "Safari is being updated/Safari cannot be opened while it is being updated." Weirdly, the error message does not have the Safari logo. Of course, the issue there is that Safari is already open. If I quit Safari, it will not re-open and gives the same error. Restarting my computer gives temporary relief (I can at least open Safari).

I have checked Software Update and the Mac App Store and there is no update for Safari listed (it would also be weird for the update to be installing while Safari is still open). I have also checked the Macintosh HD/Library/Updates folder and not seen anything for Safari. I was concerned about a virus, but MalwareBytes did not detect anything.

Any help in identifying and/or solving this issue would be greatly appreciated.