Thread:Flanqer/@comment-26828130-20190723115450/@comment-24931587-20190723192319

Custom tooltips are a bit like creating templates for basic/advanced tooltips. It saves you the trouble of having to retype stuff that's the same for every tooltip, and use parameters for the parts that can vary. For example, you could create a custom tooltip with the text "Only works with <#power#> locomotives", and then use it by typing to get a tooltip that says "Only works with steam locomotives". Or you could create a custom tooltip that displays a small table, using parameters to fill in some data values.

The main benefit of custom tooltips is faster page load times, which can be very noticeable if a page contains a lot of tooltips.