Hello, I have noticed a difference in the email message background appearance in Thunderbird (version 140.1.1 ESR) on two different computers. On one machine, the background is dark (see attachment 1), while on the other it is light (see attachment 2), even though I am using the same profile and software version. I am attaching the perfs.js configuration file along with two screenshots illustrating the difference. Could you please help identify which specific setting or option controls the dark background mode in the message view, so I can unify the appearance across both computers? unfortunately I can't find the perfs file Thank you in advance for your support.