Available since v0.1.0

fs-trigger="hover"

Stable

Fires when the mouse enters the element. Implemented as an alias for mouseenter (non-bubbling, once per enter — not the noisier mouseover).

Syntax

<div class="product-card"
  fs-assert="catalog/show-quick-view"
  fs-trigger="hover"
  fs-assert-visible=".quick-view-overlay">

When to use it

Hover-activated tooltips or quick-view overlays
Preview-on-hover UI (image thumbnails expanding, video auto-play)
Menu drawers that expand on pointer entry

Example

<button class="help-button"
  fs-assert="help/show-tooltip"
  fs-trigger="hover"
  fs-assert-visible=".tooltip">
  ?
</button>

Pairs well with

fs-assert-visible — tooltip or preview appears
fs-assert-added — lazily-mounted preview is inserted
fs-assert-timeout — cap how fast the hover reaction needs to be

Gotchas

Touch devices. There's no hover on touch — the assertion will never fire on phones and tablets. Mirror it with a click- or focus-triggered variant if you need mobile coverage.
Rapid enter/leave. Flicking the cursor in and out can produce many trigger fires in quick succession. Each starts a fresh assertion.

See also

click — touch-safe alternative
focus — keyboard-accessible alternative
Triggers index