Markdown does not interpret combo styles correctly

[hunttis]

Description
Markdown such as ***bold****italic* is interpreted as bold**italic where bold and italic is applied to the whole string instead of the correct interpretation where the first part is bolded and the second is italic like so: bolditalic

Screenshot

Sandbox
https://www.slatejs.org/examples/markdown-preview

Steps
To reproduce the behavior:

1. Go to the Slate Markdown Preview
2. Add the following text to the preview: ***bold****italic*
3. Note that the latter part is ignored, unless a space is input between the tags. This is not exactly the issue we're having, but I think it relates to our issue, where combostyles are interpreted wrong.

Expectation
That the above input would produce bolditalic

Environment

• Slate Version: 0.110.2
• Operating System: Bug noticed on macOS Sequoia
• Browser: At least Chrome and Safari

Context
Unfortunately I can't share our code, but if you have a problem reproducing this, I can try and find time to make a minimal project where this happens.