1. After placing the mouse, it becomes a hyperlink 2. Where is the height of the red box classification set?

It seems that the simplified Chinese characters use more height space. You might need to adjust the line-height CSS property.

Specifically in this composer context, you can try this CSS:

.composer-fields .title-and-category .select-kit .select-kit-header {
    line-height: var(--line-height-medium);
}

Before/After: