Safari from macOS Catalina not working on macOS Mojave

I followed this answer to downgrade from macOS Catalina to Mojave (without having a Mojave backup). This has worked well, except using the Time Machine backup made in Catalina to restore data to Mojave has resulted in getting a too advanced version of Safari for macOS Mojave:

You can’t use this version of the application “Safari” with this version of macOS.
You have macOS 10.14.6. The application requires macOS 10.15 or later.

What would be the easiest way to downgrade to a working version of Safari? I am hoping it does not involve reinstalling macOS Mojave.

Solution 1:

As jaume and ankii suggested in the comments below the question (and as per Apple Support), the way to do it is to reinstall macOS Mojave. I now have the correct version of Safari for Mojave and I don't seem to have gained any new problems doing this.

If anyone comes to this question looking to find a place to download a stand alone version of Safari for macOS, I don't think it exists - though I am happy to be corrected.