Formatting is broken following shift-enter

[miciasto]

• Searched existing issues to avoid creating duplicates.
• Confirmed that it can be reproduced in built-in themes without customized css.
• Searched http://support.typora.io/

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Describe the bug
There is a glitch when applying multiple formats to a line that immediately follows a shift-enter.

After the first format is applied, the selected region is changed, it incorrectly shrinks and no longer spans the whole line. It should have expanded to cover the closing format marker. This means subsequent formatting (or unformatting) is applied incorrectly.

To Reproduce
Steps to reproduce the behavior:

1. Enter the text abcdef on a new line.
2. Move the cursor between the c and d, and press shift-enter to insert a line break
3. Select the entire line def
4. Enter ctrl-u

Expected behavior
The result looks like this:

It should be like this (notice the selected region spans the whole line including the formatting characters):

Desktop (please complete the following information): and Typora Version:
1.9.3 on Linux Ubuntu 22.04
1.9.3 on Windows 11

Additional context
Due to this behaviour, applying multiple formats on the line will corrupt the text. More and more rubbish characters will be added to the line as more formatting is applied.