|I have used Chrome as my work-horse browser, for some years now.
Like other people commenting on this thread, I set-up a fairly complex source/topic folder hierarchy, for which I set up Chrome Filters to automatically label incoming e-mail, and I also set up Filters to label mail from myself to the same domain, or person(s). So, I can open one folder, and see all mail from, and to, a certain person, group of persons, or a specific domain (like CP).
My InBox has been on a crash-diet, ever since I analyzed what was "transient," and really didn't need to be kept for more than seven days.
This is the crash-diet:
1. for every recurring source (domain) of e-mail I considered transient, I constructed a Chrome filter that automatically labels the e-mail from that domain (or some particular sub-domain within that domain) with the label: "Delete Me."
2. Then, I set-up a simple Chrome script titled "cleanUp:" that goes through all InBox messages, and moves ones with the "Delete Me" label to the Trash, if they are move than seven-days old. See footnote  below for where I got the Script, and learned how to use it within Google Chrome.
3. Then, I set a "trigger" in the Chrome scripting facility to run "Clean Up" once every seven days.
Initially, I had to manually run the script many times from the Chrome Script window: evidently Google's servers allow a user's GMail script to run for only so long, until they time-it out. After about thirty runs of the Script, some 4000 messages had been moved to the Trash, and I deleted them.
I feel so much lighter now that my InBox weighs a little under 3000 items
 I posted the link to the resource that showed me how to use Google Scripts here on CP in the "Free Tools" section on February 23: [^]. And, that link gave me the sample code I modified only slightly in my "cleanUp" script.
"Good people can be induced, seduced, and initiated into behaving in evil ways. They can also be led to act in irrational, stupid, antisocial, mindless, and self-destructive, ways when they are immersed in 'total situations' that impact human nature in ways that challenge our sense of the stability and consistency of individual personality, of character, and of morality."
Dr. Philip G. Zimbardo, in "The Lucifer Effect" 2008: ISBN-10: 08129744