Extreme performance degradation on load

[Marc-Andre-Rivet]

First render of dash-table has become extremely slow --

1. find the problematic change
2. fix performance

We seem to be rendering hundreds of AutoresizeInput components that in turn trigger hundreds of layout evaluations by the browser.

I believe these AutoinputResize come from the Select / Dropdown.

[Marc-Andre-Rivet]

Issue is caused by the change at

dash-table/src/dash-table/components/ControlledTable/index.tsx

Line 627 in 9e1ddee

const tableStyle = R.mergeAll(

[Marc-Andre-Rivet]

The merged style object is a new object every time the controlled table renders, triggering layout evaluation on every single element of the table. Memoizing the style fixes the issue.

[Marc-Andre-Rivet]

Something is still going on. Reopening.