Hi all!
I just published a plugin that allows you to limit the file types a user can upload using the Native Bubble File Uploader and Native Bubble Picture Uploader!
For example, only let users upload .gif and .png files!
Demo page (editor is public): Limit File Types File Uploader
Plugin page: Limit File Types File Uploader Plugin | Bubble
You can always reach out to me for questions, bug reports or feature requests!