cache flow actions in browser to speed up flow editor

[tszalaj]

Inserting actions to a flow each time cause reloading them from a remote endpoint, even when actions are loaded and user tries to filter them. That is a huge waste of time and resources, as actions set can be cached and requests can be done asynchronously to update cached actions set.

Please introduce browser cache that would speed up inserting and searching (filtering) actions and make requests for actions to flow actions repository endpoint asynchronous - invisible to a flow creator.