Umbraco-cms: RTE css selectors are not properly displayed

[skartknet]

The CSS selectors created in the linked stylesheet of the RTE are not properly rendered when you enter more than 2.

Umbraco version

I am seeing this issue on Umbraco version: 8.6

Reproduction

If you're filing a bug, please describe how to reproduce it. Include as much
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Bug summary

The CSS selectors created in the linked stylesheet of the RTE are not properly rendered when you enter more than 2. The css selectors are not split correctly.

Specifics

Steps to reproduce

Create a rule in a RTE stylesheet with a selector as 'h5.text-extra-dark-gray.alt-font.font-weight-600'
and no styles.

Enter some text in an RTE and assign the previous rule from the Formats dropdown.

Expected result

I would expect a tag displayed as:
<h5 class="text-extra-dark-gray alt-font font-weight-600">some text</h5>

Actual result

The rendered element is:
<h5 class="text-extra-dark-gray alt-font.font-weight-600">some text</h5>

You can see that the third rule is not split and the dot is still there.

[nul800sebastiaan]

Hey there @skartknet - this seems like a bug, I believe that this should be possible.

I'll put this up for grabs with a caveat that debugging how Tiny works with these styles might be quite an "interesting" path to go down. 🙈

[kjac]

Oh nice one! I can repro, fix incoming.

[kjac]

PR in #8164

[nul800sebastiaan]

Fixed in https://github.com/umbraco/Umbraco-CMS/pull/8164