Hi. 

I tried to burn an .iso image to a DVD using k3b version 19.8.3 on my Fedora 32 X64 bit Cinnamon edition.

When I selected the .iso image, I received a window inform me the following message: "Type of image file is not recognizable. Do you want to burn it anyway?"

I gave him okay (Yes) to burn it. But in dialogue, I changed choice of "Image Type" from "Auto Detection" to "ISO 9660 filesystem image". Then activated "verify written data" then started the burn process.

Burn process started & completed without error message, & verification process also completed without error message. I opened the DVD, & it seem that process run okay. However, I'm not sure if an error had been happened in burning process or not! For that I do not know what I have to do with resulted DVD: depend on it or dispose it! Whay this message appeared & what it mean? How & why k3b did not recognized this .iso image?

File of problem is available on Internet from this address:
https://hugesharing.net/5sy4li6vnot7/Combat.Helicopter.Surgical.Strike-PLAZA.rar

You have to download file, then extract the archive, & finally burn the .iso file that located inside the folder resulted from extraction process. The .iso file have the following name (with the .iso extension):
plaza-combat.helicopter.surgical.strike.iso

I tried to rename it to "test.iso" but same result!

I attached the debugger-output file so that to be seen by you.