The uFL connectors on a lot of popular VTXs break off quite easily.
I’ve managed to rip the connector off the board of my TBS Unify and Matek VTX. If the socket on the board also comes off, it renders the transmitter useless.
Soldering the pigtail is the best solution in this situation, and while that might be almost impossible on the Unity transmitters, Matek have made it rather straight forward – even illustrating it on their website – thanks Matek!
The first step I would recommend is covering the connector on the PCB before soldering anything. This will prevent any bits of solder shorting the circuit, which would be a pain in the butt to fix later on.
Above the connector are three pads. GND ANT GND. The illustration above makes it pretty clear; you need to cut the end off of your pig tail, twist the outer mesh into two strands and solder them to the GND pads.
The inner ‘core’ should then be soldered to the middle pad. That’s it!
You may also want to use some putty or cable ties to secure the pigtail to the board in case it gets pulled in a crash.