Blender will crash if a file with an Alpha Over node was saved in 4.4, then in 4.5 alpha, then back to 4.4. This is because the node was missing forward compatibility code that allocates storage that was necessary for the file to load correctly on older versions. This was essentially missed inb62ef2cdd6and976efdcac9. Pull Request: https://projects.blender.org/blender/blender/pulls/141873