I think you can make the interface more clean by adding a button or just a link to subscribe to (unsubscribe from) a channel:
It should affect both /watch and /channel pages.
If it possible I would also add the total number of subscribers like YouTube does it:

And channel thumbnails can be helpful as well.
Oh, and maybe use javascript or something to send the "subscribe signal" to Invidious instead of relying on redirecting the user to the main page, etc.
Sounds good!
I understand wanting to use javascript, but the main issue I have is that it won't work for people running any combination of NoScript, uMatrix, etc. I think the redirect system just needs to be fixed instead of replacing it with JS. I think that is a bigger issue with subscriptions than with comments (which are loaded with JS) because I consider subscriptions a core functionality of the site, so it should work for as many people as possible.
But the thing is, it's very easy to load a script that replaces the current 'Subscribe' button with a non-redirecting one.
You can always send out the redirecting button by default, and send out a script that replaces/modifies it.
You can also test whether XHR's work once in a while, if scripts are enabled.
Or the very least, something could be worked out so that playback continues from the point you clicked subscribe.
That's fair enough, I think I spoke too soon.
Added with 1a39faee75cb1c5ff8545444f3e653e2958d5452.
Thanks for this!
I don't think the blue color fits for it though.
Currently this is the only 2 colored things on the site are the blue Subscribe button, and the Player volume slider on the Preferences page.* The rest is black / white / gray, depending on the color scheme.
I think a shade of light gray/dark gray would fit better than the current blue one.
That's true, although you could make the same argument for YouTube's interface:

I think it makes sense for a "call to action" per se to be in a contrasting color, trying out some of the other main colors (grey colors) used elsewhere don't seem as appropriate.
@dimqua has made some very nice improvements to the color scheme, I'd be curious if he has any thoughts on this.
@omarroth Could you add channel thumbnails too?
Also I think it's better to replace Subscribe to video.author button with Subscribe button, like:

Besides, as you can see in the OP, there is an "official" mark after BBC News channel name, meaning that this channel isn't fake. Can we have it?
@Discookie @omarroth What about these colors?

a.pure-button-primary {
background-color: #a0a0a0;
color: rgba(35, 35, 35, 1)
}
a.pure-button-primary:hover {
background-color: rgba(0, 182, 240, 1);
color: #fff;
}
I'd personally go with #f0f0f0 for background color - the contrast is too low with a0 and I'm having trouble reading it.
Other than that, I like it, and I think it fits the site a lot better!
I'd personally go with #f0f0f0 for background color - the contrast is too low with a0 and I'm having trouble reading it.
Only issue is with light theme, the button looks like this:

If it would be better to have seperate colors for light and dark themes, I'd be open to it. @dimqua's additions added with 3c634d9.
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@Discookie @omarroth What about these colors?