I want a man page viewer with more features than man(1).

Specifically, I want something that:
1) Prioritises the current man page in its title, so I get meaningful taskbar entries like "somecommand manual" instead of generic "currentuser : man -- Konsole".
2) Has a sidebar with ToC/headings for the current man page, so I can quickly navigate.
3) Has bookmarks so I can mark commonly referenced sections and easily return to them, even when there's no nearby header.

And it needs to retain at least the following features of man:
4) Starts instantly and remain entirely offline (i.e. nothing web-browser-based)
5) Not be a change in screen brightness when switching to it - i.e. allow light text on dark bkg, like my terminal.
6) Text that is suitably formatted/selectable/searchable/etc.

My searches have revealed a few alternative man page viewers that don't meet the requirements: xman, gman, yelp, khelpcenter, man helper, mangl.

Can anyone introduce me to something that satisfies the above, or is this yet another time when I'll need to waste time building my own solution?

Why do you consider writing software that is useful to yourself a waste of time?

Because it's yak shaving; I'd rather be spending the time on other things.

Also, it feels like this is something that someone must have done already at some point in the past two decades - nothing I want is an obscure/niche feature - so if I could just find that existing solution I wouldn't need to duplicate the effort.

This thread from AskUbuntu contains several suggestions.

Man is usually a way for those already trained to get help. It isn't designed to be a learning tool.

Usually all that data for it comes from the programs. man is just a way to display it. One could make a web reader out of it that is entirely offline.
https://askubuntu.com/questions/3392...-a-web-browser
There are some small fast browsers to view those.

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Just because it hasn't been mentioned yet:
https://hiphish.github.io/blog/2020/...d-on-steroids/
I like the quick previews in the search.

what if you download the full man package offline and use it from browser (like this: https://linux.die.net/man/)

2 members found this post helpful.

Another approach is the 'info' command. It is certainly more usable in some ways than 'man', though it may not meet the desires of the OP.

2 members found this post helpful.

Have you tried Konqueror's man viewer? Type into the url address place (and, No, you don't have to be connected to the internet). Also works for