It happens quite often. You are cycling and suddenly the battery of your bike computer is dead. Or you accidentally press 'save ride' in between at a coffee stop. Or whatever. If your computer quits, you can just continue recording via the app on your phone. But whatever the cause, you end up with two files. By default, these are saved as separate rides on Strava, but it's not really pretty. Few people want "Summer evening ride part 1" and Summer evening ride part 2" in their timeline. You probably want it to be one anyway. But how do you do that?
This simple little tool allows you to combine multiple files into a ride: https://gotoes.org/strava/Combine_GPX_TCX_FIT_Files.php. Granted, it's pretty basic, but those few times I needed it worked just fine. Up to twenty files can be pasted together. The formats are FIT, TCX and GPX. For the normal Strava user, this is fine. Uploading to Strava is included and otherwise it is self-explanatory. At least this way you keep your Strava history tidy.
Here you'll find more Strava tools, by the way. Good luck.