Punctuation marks causing Markdown bold display to fail

[sk-or-v1-contents]

@renato

if you used the UI to build this situation (**text.**text), it displayed correctly on the rich editor, but cooked as plain-text

Can still reproduce this bug, the punctuation is only moved out after I switch to Markdown editor or post.

Test with rich editor: text.text

the punctuation is still initially bolded