FCP Inspector - Custom Parameter

Reproduction

Creating a custom parameter view with the kFxParameterFlag_USE_FULL_VIEW_WIDTH flag produces strange behaviour in Final Cut Pro (FCP). Before we start here's my plugin for this debug session, I'm replicating Motion's inspector row appearance.

The issue is when a filter effect is added above my custom full-width plugin, the keyframes no longer show for that effect. If you reverse the order the keyframes show again.

Now, it doesn't effect just the single once above it, but all of filter effects (well with a caveat, 1 sec).

This only happens with kFxParameterFlag_USE_FULL_VIEW_WIDTH , you can have a custom view for the parameter section only to avoid this issue.

Okay, but what happens if I have 2 of my custom plugins, do they also break the keyframe controls? No, a second instance of my own custom plugin shows the keyframe controls as expected.

🫤 Workaround

There is a cheeky workaround, simply sandwich another custom instance on the very top of the effects chain, you can even disable it. Welcome back keyframes!