Summary

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

• Bugfix
• [ x] Featureconfig $siteTitle by frontmatter #3086
• Code style update
• Refactor
• Docs
• Build-related changes
• Other, please describe:

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.)

• [x ] Chrome
• [x ] Firefox
• [ x] Safari
• [ x] Edge
• [ x] IE

If adding anew 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 afeature request issue first and wait for approval before working on it.

Other information: