Project overview file upload not working in web browser
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### Summary
File upload in project overview in web browser doesn't show file selection window
### Steps to reproduce
- open a project on gitlab.com
- go to "Project overview" - Details
- click the "plus" button and choose "Upload file"
- in the popup, click the "click to upload"
### Example Project
https://gitlab.com/pfiala/fileupload
### What is the current *bug* behavior?
No file selection window appears, i.e. the file upload cannot be performed
### What is the expected *correct* behavior?
File selection window opens as if the same steps to upload file are performed in Repository - Files page (https://gitlab.com/pfiala/fileupload/-/tree/master)
### Output of checks
This bug happens on GitLab.com
issue