Thunderbird 91.5.1 (64-bit), Windows 10, "When new messages arrived->Play a sound" enabled. Until some updates ago, Thunderbird emitted the sound only when new emails came. Now it does that when RSS feeds get updated as well. Is there a way to disable sound alerts for RSS messages only? I tried disabling "When new messages arrived->Play a sound", while keeping "When new messages directed at you arrive->Play a sound" on, but in this case all sound notifications were gone.