Tab contents stops rendering
Once in a few days the following bug occurs: a page stops rendering, most of its images disappear, and the last visible contents stuck on the screen. I can scroll it up and down, but there's nothing there, it's just filled with background color. After refreshing the page (F5) it works normally. See the video for an example: https://streamable.com/ba2e3
Disabling hardware acceleration is not a solution because with all the tearing it makes the browser basically unusable.
System: Windows 10 Pro 64-bit (v 1803, build 17134.706), GeForce GTX 970 (driver version 425.31), 8 Gb RAM, i7-4790 CPU Firefox version: 66.0.3 (64-bit)