fix: adjust intersection observer threshold for sticky class toggle

[sy-records]

Summary

During test #2635, it was discovered that enabling cover and placing its content in the readme causes infinite flickering.

Related issue, if any:

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

For any code change,

• Related documentation has been updated, if needed
• Related tests have been added or updated, if needed

Does this PR introduce a breaking change?

• Yes
• No

Tested in the following browsers:

• Chrome
• Firefox
• Safari
• Edge

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Project	Deployment	Preview	Comments	Updated (UTC)
docsify-preview	Ready	Preview	Comment	Nov 26, 2025 3:49am

[paulhibbitts]

Thanks @sy-records , happy to help test but unclear of the setup I need to try?

[sy-records]

Directly modify the README in the docs using the content he mentioned to reproduce the issue.

[paulhibbitts]

Thanks @sy-records , I've made a new Sandbox and used the build from #2635 but do not see the issue, am I still missing something?

https://codesandbox.io/p/sandbox/docsify-v5-template-sticky-class-toggle-l6wrkj

[sy-records]

Just a little content is needed.

2025-12-01.14.39.33.mov

[paulhibbitts]

Thanks very much @sy-records , I was finally able to replicate the issue:

2025-12-01_07-01-29.mp4

I tested with the PR build, and the issue looks to be addressed:
https://paulhibbitts.github.io/docsify-v5-rc/#/?id=codeblock

Good catch! Thanks, Paul

[trusktr]

What happened with this?

[sy-records]

Since I submitted the PR from a forked repository, deployment requires approval.