FilterTags editor UI unusably slow in larger projects

[YoriKv]

The FilterTagsDrawable class responsible for drawing the UI for the FilterTags property field runs so slowly as to be unusable in larger projects. The reason for this seems to be that the list of choices for the dropdown calls the function GetAllInteractibleObjects() every OnGUI (every frame, or possibly even more often). This function searches all objects in the current scene and also all objects in the project assets and for larger projects takes a significant amount of time.

Solution would be to cache the results of the process that requires GetAllInteractibleObjects() so it only gets called the first time the UI is rendered instead of every OnGUI.

[taylorjames9]

This is a really good suggestion. We've been looking for a way to improve UnityUI with interactable objects. We've been steering people away from using UnityUI with HUX/MRDL, but we lose far too much built in functionality by doing that.

[Railboy]

We'll be replacing this with an Attribute so developers can choose when & where to draw the dropdown. This will eliminate the need for GetAllInteractibleObjects altogether.