Why is this important?
To avoid opening emails before they’ve been security checked, OnINBOX adds a filter rule that moves all incoming emails to an OnINBOX Processing folder. After each email has been processed, OnINBOX moves it back to the Inbox, unless it identifies a filter rule in place that archives the message (skips the inbox) and adds a custom label.
Are there any limitations I should be aware of?
When we move emails out of OnINBOX’s processing folder, we check for any labels that Gmail has applied to the original message as part of your filter rules to determine whether we should leave this message archived, or put it into your inbox.
This means that filter rules that archive messages will only work if the rule also adds a label to it.
For example, if you had a filter that automatically archived all messages from a particular sender, but don’t add any labels to these messages, OnINBOX will return this message to the inbox instead of archiving it.
Another scenario to be aware of is where there are two filters applying the same custom label for different conditions, but only one of these filters requests the email to be archived. In this situation, OnINBOX will always move messages of this label type to the Inbox.
For example, if a user has two rules set up for the label "Red Sift":
One filter rule simply that labels all messages from "redsift.io" as "Red Sift",
One filter rule that archives all messages from "firstname.lastname@example.org" under the "Red Sift" label.
In this situation, OnINBOX is unable to differentiate the criteria for each filter, so it will move all emails labelled “Red Sift” into the inbox and not archive the "email@example.com" ones.
To get around this, you would need to have separate “Red Sift” and “Red Sift Marketing” labels, or use an additional rule that applies a “Archive” (or other alternative label) to ensure the email you’d like to have archived.
Why do these limitations exist?
Google uses a unique criteria matching ‘regex-like’ system that OnINBOX is unable to understand. Therefore, when situations come up where it’s not clear to OnINBOX whether a message should be archived, it will move the message to the inbox to be on the safe side, to ensure you never miss a single message.