Extend audio clips with custom length silence buffer tails, even past the end of the clip

[belisoful]

Apple Feedback Assistant ID: MISSING!

Is your feature request related to a problem? Please describe.
I'd like to give a sound a reverb but the sound ends too quickly. There is no room at the end for the persistent reverb or echoing sound. By adding custom lengths of silence at the end, I can add a reverb to the sound that will fill that silence.

Describe the solution you'd like
I would like all sounds to be able to simply "extend" with silence. I'd like to just add silence of any length I need to the end of all sound clips. It would be its own sound clip as an extension of the main clip. The "silence extension clip" would display any remaining sound effects adding sound to the silence, as per typical where sound clips show their wave form after effects are applied.

The silence buffer should not be limited by the length of the parent clip, but extend it.

Obviously, this would extend to a video clips audio track too.

Describe alternatives you've considered
Editing the sound in Audacity to add a silence buffer at the end... but the sound is built into FCP, so it's not revealing in the finder.

Additional context