[Users] Moving emails to a common inbox

[clml.omentum at slmail.me]

On Windows 10 1809, with Claws 3.17.8, I have a multiplicity of email
accounts.

I have set up a MH common folder, which has an inbox, etc.

I have, for each email account I want it to apply to, right-clicked its
inbox and set up, under 'Processing', a rule, applying to all emails
in the inbox, to move them to the common inbox.

In each account it applies to, I have checked the option 'Filter
messages on receiving' on the 'Receive' tab in the Account
Preferences.

I expected emails in those account inboxes to be moved to the common
inbox *as they arrive*. But they only get moved when I enter the
specific account inbox and click on the message. Which is tiresome.

(I am trying to duplicate what The Bat! does with its common virtual
folders.)

Is there a way, please, to get them to move into the common inbox when
they arrive? Am I missing something? Is there a better way to achieve
this?

Thanks,

omentum