If a data-block referenced the same shared data more than once, it used to be
written multiple times. This worked out so far, because the written data is
always the same. So when reading the file, it doesn't matter which written
buffer Blender decides to read on. However, this makes the .blend file look
corrupt and leads to memory leaks on load (#125001).
Pull Request: https://projects.blender.org/blender/blender/pulls/125489
26b7ae888b