Hi,
I'm seeing a graphical disruption on my 255 Music, similar to what I saw in the 955 thread (https://forums.garmin.com/sports-fitness/running-multisport/f/forerunner-955-series/306930/graphical-corruption---dashed-horizontal-line-across-watch-face). I've seen it intermittently since I got the watch, and it happens both on stock faces and other faces.
Here are some photos:
All-
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All,
Please see our recently released beta software for a fix addressing this report. If you prefer to not install this beta software, we hope to be rolling out a public software update soon, though I…
I have the same problem since the last update! 
Just got it again, after updating to 12.23 - this time it was slightly thicker.
It also happens during longer trainings, a solid black line
I have the same problem since the last update!
They’re getting more interesting 
