Re: Email clients
With regard to Gmail and POP, if it's been enabled since "Day One" of your account's existence, even if you have not used POP, you have two choices as to how POP will behave if you were to configure an e-mail client program to access the account that way:
All of my Gmail accounts are old enough that POP had still not fallen out of favor when they were set up, which was at least 10 years ago at a minimum. At the top of the POP section there is a line that reads, "Status: POP is enabled for all mail that has arrived since <account creation date here>."
You are also given a choice about what Gmail should do with it's own copy when a message is accessed using POP via an e-mail client that reads:
When messages are accessed with POP, followed by a dropdown box with the following choices:
1. Keep Gmail's copy in the inbox
2. Mark Gmail's copy as read
3. Archive Gmail's copy
4. Delete Gmail's copy
If one plans to access mail from multiple locations on multiple devices using e-mail client programs IMAP is the way to go, and unquestionably. It keeps things "in sync" across all devices provided that one's filtering is done on the e-mail server side (preferable, as that is performed as the messages arrive) or you have one of your clients that runs 24/7 that applies the filters you set up on the client side to sort messages into your IMAP folders which are seen by all clients. The second option is far less preferable since if that client that does the sorting goes offline then the sorting itself stops.
I tested all this out via Thunderbird the other day and while it's a simple matter to create IMAP folders from within Thunderbird itself creating the filters in Thunderbird does not cause them to be created on the server side, but only within Thunderbird, so if I were not running that instance of Thunderbird to be the "master sorter" then other clients would be seeing all mail land in the inbox, untouched. I suspect the same would apply with MS-Outlook, but haven't tested it out yet.
For those using Gmail I wrote a tutorial a couple of years ago on how to create filters and IMAP folders (which Gmail calls labels) under Gmail's web interface with a screen reader: Creating IMAP Labels (Folders) and Filters for Gmail. Using that method guarantees that the Gmail server will be doing all of the filtering and sorting for you before any one of your e-mail clients, whether ones you're currently using or might set up via IMAP access in the future, will ever gain access to the latest incoming messages.
Brian - Windows 10 Home, 64-Bit, Version 1709, Build 16299 (dot level on request - it changes too often to keep in signature)
The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth.
~ Niels Bohr