I've basically given up trying to understand how and why this is supposed to work. It's a real pain when it happens, so I try very hard to not have to change anything, but if and when it's necessary, I just recreate from scratch the object in question, whatever the complexity. It's slow and laborious, but still quicker and more likely to succeed than bashing my head against the 'Re-Import' brick wall.
Even this is not without tribulations, though. I have valid 3D objects, in GLB format, from Blender, which, when created in Godot, do not always have their Textures. I have to mess around with 'Do I need to make a 'New Inherited..?', or can I 'Open Anyway..?'. Whichever way, it's more likely than not that the GLB will not have its Textures, or even its Meshes, and, if I get to edit, the Texture options for Albedo are greyed out. Sooner or later, I strike lucky and the Textures show up, but exactly which path brings this about seems, to me, to be shifting sands. I really don't know why it has to be so complex for what seems, again, to me, to be a fundamental 'first step' that everyone will be going through, to create any 3D scene. I suppose everyone else has a solid work-flow that does away with this, but I'm blowed if I can find it. Yes, I've followed tutorials, videos and explanations (often too technical for my tired pea brain to latch onto, but that's my fault, not theirs...), and have tried, in the past, to note down the steps needed. I started this Project in 2021, and have, now, several hundred Scenes, Animated Beasts, Humanoids and Items, so I should, one would think, start to know how to do the most basic creations by now. Alas, no; there is much I do not understand.
Enough..! I've still my 'Save' and 'Reload' options to finish off. The whole Project is nearing completion, and, despite this 'rant', I've learned a lot and received much help from this Forum, and other sources. It makes it all the more frustrating to have these niggles, when they occur, but... Whatever. It's still the best system I've come across, and does an excellent job with my modest Projects, ...
Onward and upward...