I think this is actually different than the “tooltip” that is displayed when hovering a menu.
But we indeed need a “tooltip” element in the UI, some kind of a mix between floating group and focus group that could be attached to an element and only shown when hovering this element or the tooltip itself.
I would thus suggest to change this thread title to something like “Adding a tooltip element in the UI designer”
Note that this feature has already been asked in the following posts:
http://forum.bubble.io/t/does-bubble-support-tooltips/6536
http://forum.bubble.io/t/dynamic-text-with-ajax-tooltips/8535/3
http://forum.bubble.io/t/easy-tool-tips-in-the-editor/7918
http://forum.bubble.io/t/how-to-get-hover-effect-from-title-attribute-with-links-and-icons/2638/6
Some solution might be to use a conditional “when X is hovered make this element visible” on a floating group, but then it would not be placed relatively to a specific element (as opposed to what is expected for tooltips), which causes responsiveness issues.
On the othe rhand, focus groups can be positionned relatively to an element, but do not have a “make this element visible” action in the conditional pannel…
This request is somehow related as well to other requests looking for navigation menus that show when a menu item is hovered.
+1 for adding that !