I've been having the same issue while using the Jumpgate beta as of yesterday, but not with a non-Jumpgate game that I was testing with. When I initially use the Measure tool, it looks perfectly fine like the image below. If I press another option in the left sidebar though (except the Turn Order or Dice button), the line will disappear despite Linger being on. The same is true for the other Measure shapes. Clicking back onto the Measure tool after that has it look like this, where the dot at the start of the line, and the arrow-head no longer exist. If I try to extend the line with mid-points, the dots in the middle also don't exist, and the arrow-head still doesn't exist. Basically, all the same issues persist, along with the line looking weird.
