In the new React implementation of the release relationship editor, only some tracks are loaded for big releases. It is an improvement over the previous Template Toolkit (TT) implementation which wasn't able to cope with some very big releases. However, it now requires the user many clicks to load all the tracks when needed for batch-editing, which is a regression compared to the previous TT implementation which was working smoothly for reasonably big releases. These issues have been reported as MBS-12873 and MBS-12875 during the beta and have been quickly addressed by disabling the features that require tracks to be loaded and accompany it with an help message.

The longer-term solution is to automatically load what is needed when using such feature. Of course, it should be done in a safe way for the server that doesn't stress it too much at once. If it requires a bit of time, a progression bar can even be considered.