I have noticed when using bitrise.io recently that sometimes when I get down a few screens on a very long log, it doesn’t render the background correctly. Sometimes this seems to be triggered by resizing the window, other times it happens on initial page load. I think I’ve only seen it for running builds. Sometimes reloading fixes it, sometimes not.
It appears to fix itself after the build finishes.
Hovering over a line of text causes the background to render under just that line. All the text is there (
Select All allows it to be seen) - it’s just impossible to read over the grey background: