zooming with two fingers in Chrome mobile causes the panel to render badly

[umbe1987]

Apparently this happens only in Chrome when zooming in or out the map with two fingers on mobile.

Problem
the toc looses the opacity slider and legens under each layer.

Cause
Acoording to openlayers/openlayers#9105, too many change:resolution events are triggered when zooming with two fingers.

Solution proposed
Using debouncing in JavaScript.

• View propertychange "resolution" issue with Chrome openlayers/openlayers#9105 (comment)
• https://css-tricks.com/the-difference-between-throttling-and-debouncing/
• https://www.npmjs.com/package/lodash.throttle
• https://john-dugan.com/javascript-debounce/