Callout is slow

[richardtagger]

Looking at flame graphs when debugging typeahead performance reveals hundreds of milliseconds spent recalculating styles in Fabric's Stylesheet.js. The root cause appears to be originating from Callout. Current approach will be to ditch use of Callout for type ahead - we actually don't need the things it provides such as animation, and positioning logic and are better off using an absolutely positioned `DIV with a border radius + shadow. However, future features that are highly interactive and re-render on keypresses may encounter similar issues.

Chrome Perf Profile.zip

[swese44]

please report this in Fabric. we get things like positioning + beak for free and it would be ideal to get perf issues fixed in the Fabric repo rather than own this ourselves

[richardtagger]

Well we don't use beak or positioning for the editor, but yes we'll use Callout for other things. I will report it to the team