Applied formats should produce optimized HTML

[gziolo]

Describe the behavior
When you apply multiple formats to the text when using RichText. It doesn't always produce optimal HTML code. In many cases the order of application matters producing different HTML. In the case I recorded, it produces two links instead of one.

To Reproduce
Steps to reproduce the behavior:

1. Create a new post.
2. Type a few words in a paragraph.
3. Apply bold to one of the words.
4. Apply italics to the part of the bolded word.
5. Apply link to the full bolded word.
6. You should see something like the following when checking HTML source:

<p>My <strong><a href="http://localhost:8888/?page_id=2">te</a><em><a href="http://localhost:8888/?page_id=2">xt</a></em></strong> to test</p>

Expected behavior
Wrap text with only one link in all cases, no matter in what order formats get applied. The HTML should look like:

<p>My <a href="http://localhost:8888/?page_id=2"><strong>te<em>xt</em></strong></a> to test</p>

Screenshots

Desktop (please complete the following information):

• OS: macOS Mojave
• Browser: Chrome
• Version: 70

[gziolo]

@iseulde, any thought on this one?

[ellatrix]

I thought this has already been reported once. Until now I considered this low priority. I can work on this for whatever milestone needed.