we are using attachment plugin into our website.
And we migrate that site from 4.30 to 4.50 but after migration we getting issue like as per below image when some one click into PDF file from product details page.
Same case still working fine into 4.30 as of now so we don't know what going wrong into some products only.
This is admin side SS : https://prnt.sc/6WI4TmnMh7hI it's same as 4.30
So please let me know if you want any further info or solution for this issue.
Thank you for reaching out to us!
The download URL should be a valid URL, so please try adding one.
I have reported this to our developers as well, so they can add a validation for a correct URL and to display a message that this should be a valid URL.