Welcome the Technical Support section. Help us in assisting you by providing us with a concise and descriptive elaboration of your issues. Be specific and if possible, provide us with a step-by-step instruction in replicating your problem.
I'm running 4.3.3 and its not allowing me to change the images for Default cover nor Default avatar under the profile page. I select X to delete the old image and use Choose to select a file from my machine for uploading but its not accepting the file upload. It just does nothing.
Would you mind provide me backend and FTP access please so I can inspect this issue directly.
1. Edit your first post.
2. Click switch below main text field: prntscr.com/fk3hdg
3. Provide your site details: backend URL, admin credentials and FTP: prntscr.com/fk3hwz
4. Let us know that you provided credentials by posting in the same thread.