I'm adding support for this plugin to my colorsheme and everything appears to be working as expected.

However, I've found the following three groups are not respecting my overrides (and staying as the defaults):

• HelpviewTagLink
• HelpviewOptionLink
• HelpviewMetionLink

All the other highlights accept my changes, just not these three. I've checked the values with :Inspect and I've definitely got the right ones (95% sure 😉).