Plex does offers a selection of colors to use, but missing the most important one: Grey. Grey is the default sub color on pretty much all 4K HDR discs. Reason being that with HDR the brighter colors glow.

Which client type? Because grey is available in some clients already.

SRT Colors

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Add a light gray subtitles option for LG webOS Feature Suggestions lg-webos , subtitles	4	86	July 30, 2023
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