Fix: Properly Maintain Selection of Keyframes When Inserting / Removing Hold Frames.
Related Feature: Preserve multi-frame selection when active frame changes. Useful for preserving the users selection on scrub, but also less error-prone when dealing with modifying the user selection while concurrent "switch-time" operation is running. Insert Keyframe Bug: BUG:404519 Maintain Multiframe Selection Wishlist: BUG:388779
Showing with 40 additions and 3 deletions