Hi velvet,
I checked the code and I found a new mobile property for that feature. It was undocumented and pretty forgotten in the last changelog, so thanks for your feedback 
To enable previous behaviour you only need to set a ZxMobile property by typing the following command as zimbra user:
Code:
zxsuite mobile setproperty ZxMobile_ImapDeletedFilterEnabled true
The default value for that property was set to false because formally those messages are not really deleted, but only marked as deleted (But of course we need to document this feature).
Note: when you enable this property, only new imap deletions will be affected by the filter 
Have a nice day.
D0s0n
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