fix #1032

[csu-feizao]

Summary
fix#1032

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Build-related changes
• Other, please describe:

If changing the UI of default theme, please provide the before/after screenshot:

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)

You have tested in the following browsers: (Providing a detailed version will be better.)

• Chrome
• Firefox
• Safari
• Edge
• IE

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature
• Related documents have been updated
• Related tests have been updated

To avoid wasting your time, it's best to open a feature request issue first and wait for approval before working on it.

Other information:

---

• DO NOT include files inside lib directory.

[anikethsaha]

Thanks for the PR. Please add test if possible ! I will review it soon.
Also make sure it doesnt break for special cases like _, -, >, . etc

[anikethsaha]

I have tested this locally, the bug mentioned in #1032 still persist (the expand issue and highlighting as well). Try re-check and test it against this demo

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[sy-records]

@csu-feizao Can you fix the problem?

[enzy]

This is just 2 line change (see diff). Can we create a fresh PR and merge that please?