[YouTube] Implement bold/italic/strike-through support

[FireMasterK]

• I carefully read the contribution guidelines and agree to them.
• I have tested the API against NewPipe.
• I agree to create a pull request for NewPipe as soon as possible to make it compatible with the changed API.

Todo:

• Tests

[AudricV]

Except my question below, LGTM!

[Stypox]

This does not seem to work well for video descriptions. Calling getDescription().getContent() for this stream returns this description (I omitted most of it in [...]):

[...] a daily message from me: &lt;a href="https://www.youtube.com/c/yogawithadriene/community"&gt;https://www.youtube.com/c/yogawithadr...&lt;/a&gt;<br><br>SIGN UP at &lt;a href="https://do.yogawithadriene.com/center"&gt;https://do.yogawithadriene.com/center&lt;/a&gt; to receive [...]

As you can see the <br> tags are correct, while the <a> tags have < and > instead of < and >. So HTML renderers interpret those as escaped characters instead of as tag delimiters.

[FireMasterK]

This does not seem to work well for video descriptions. Calling getDescription().getContent() for this stream returns this description (I omitted most of it in [...]):

[...] a daily message from me: &lt;a href="https://www.youtube.com/c/yogawithadriene/community"&gt;https://www.youtube.com/c/yogawithadr...&lt;/a&gt;<br><br>SIGN UP at &lt;a href="https://do.yogawithadriene.com/center"&gt;https://do.yogawithadriene.com/center&lt;/a&gt; to receive [...]

As you can see the <br> tags are correct, while the <a> tags have < and > instead of < and >. So HTML renderers interpret those as escaped characters instead of as tag delimiters.

I think this might be a side effect of #1005 instead 🤔

[TobiGr]

Escaping text right after if (html) { should do the job, i guess.

[FireMasterK]

Escaping text right after if (html) { should do the job, i guess.

We already have such a check, yet this happens. Will need to investigate further.

[TobiGr]

that's not what i meant. see #1006