Related: #4997. Follow-up to #5739 and the review comment.

Summary

Icon tooltips added in #5739 always used Element Plus's default dark appearance and opened after only 300ms. They now follow the active MarkText theme and wait longer before appearing when the pointer passes over a control.

• Use the theme's floating background, border and shadow. Strengthen the theme's title text toward black in light themes and white in dark themes so small labels remain readable; rendered contrast across all 33 bundled themes is at least 4.83:1.
• Use compact padding and an outline without an arrow, inspired by VS Code's workbench hovers.
• Match VS Code's workbench hover defaults: 1500ms on macOS, 500ms on Windows/Linux. Layout reference: hoverWidget.css.

The existing Enter/Space handling, Escape dismissal and accessible names are preserved.

Type of change

• Bug fix (non-breaking, fixes an issue)
• New feature (non-breaking, adds functionality)
• Breaking change (causes existing functionality to change)
• Documentation update

Test plan

• New E2E coverage for brief hover cancellation, live theme changes and the absence of an arrow. Keyboard-only focus is checked beyond the new hover delay.
• macOS Electron verification: 17 E2E cases passed; one Windows-only window-controls case skipped.
• Related unit tests: 8 passed.
• pnpm run build:unpack, pnpm run typecheck, pnpm run lint (no errors; existing warnings).
• Additional rendered contrast check across all 33 bundled themes.

Screenshots

Light	Dark

Notes for reviewers

The styling is limited to IconTooltip; it does not restyle other Element Plus popovers. The popper is teleported to body, so its class is styled globally within the component.

By submitting this pull request, I confirm that my contribution is made under the terms of the MIT license.