Design Studio not responding for a while when adding a custom folder with many images

Steps to reproduce:

• Create a project
• In Content library - User assets, click + to add a custom folder
• Select a folder that contains many images (I selected a folder with 288 images, size of the folder content 1,39GB)
• ->Design Studio goes into "not responding" state
• After ~2minutes, Design Studio recovered and custom folder was added
• Expectation is that this "not responding" state would not happen at all and folder would be added quicker.
• While loading a folder with lot of assets, some progress bar or other indication that "something is happening" would be nice.