Hi,
Yesterday I finished a half marathon with my Forerunner 955. However, when crossing the starting line I started the run activity which instantly caused the watch to crash to a black screen get stuck in a boot loop. I spent my first kilometer or so with my phone fiddling with the settings until I found that the watch would exit the bootloop when turning off the event sharing feature. I also had PacePro and Livetrack active, these didn't seem to give any problems later on.
After disabling it the watch started as normal and I could finish the event, although I missed the track misses the first part of the race (and my PR ).
For info: I'm running version 22.24.