ansi log escaping seems to break at line 500 and later

[q66]

When you have a log with ansi colors in it, the escapes stop being interpreted at line 500 and after in some manner.

I found that when I saw our firefox build output tends to be kinda broken, e.g. like https://build.chimera-linux.org/#/builders/5/builds/232/steps/5/logs/pkg_contrib_firefox_128_0_2-r0 - you can see some of the sequences are not being interpreted, sometimes the whole output just becomes blue.

I tried launching a local buildmaster where I just cat'd a portion of the log file. I noticed that things kept looking broken until I removed enough lines that the first broken line started before line 500, at which point it started rendering correctly again. The content of the lines removed does not seem to matter.

This is with the new react UI. With the old angular UI we had the same breakage; however, it seemed to be less affected as some stuff that previously rendered okay no longer renders okay now, but that's likely a separate regression. I haven't yet tracked down a good sample for that.