Problem with images not added to collection on import with multiple cards

I've been having an issue for years, and I keep hoping it will eventually be fixed. If I select "add to a collection" during import, it will work fine if I only import images from one memory card. However, if I import one card of images and they are still processing, for example, creating 1:1 previews and smart previews, and I import a second memory card while the first set of images is still processing previews, one or both sets of images will not be added to the collection.

It's not a big deal. I go into the folder in my library and drag them to the collection manually, but it would be nice if this issue didn't happen. I've had this issue through multiple installs over years so I can't be the only one to notice it.