jquery.tipsy is pretty old, pretty awkward and pretty ugly. We should stop using it in our interfaces. OOUI's popups implement most of the features we'd want.
For simple contents a title attribute without payload of an extra JS dependency is sufficient as well.
We deprecated the module in 2017 as part of T142418
(Old/minimal documentation page at https://www.mediawiki.org/wiki/Tipsy )