I've encountered a couple situations where the name of a layer in my comp will somehow "compress," with the displayed label scaling down so that I can't even see the name. Here's a screenshot of the most recent attack of the compression monster:
It's only happened a couple times, and both times I was looking elsewhere when the change occurred, so I couldn't pinpoint a specific set of steps that led to the problem. The first time it occurred, I tried numerous things to fix it, but the problem stayed put. The most recent time (earlier this morning) I collapsed all layers and their contents, and that somehow fixed it.
This is happening in the latest release of HitFilm Express 2017 on my Mac. System specs:
Mac Mini (Late 2014)
Mac OS X 10.10.5
2.6 GHz Intel Core i5
8 GB 1600 MHz DDR3
Intel Iris 1536 MB