K9 still lacks message filtering capability, and the proposed workarounds are useless to me.
I see that there are several threads on this topic from the past few years, and that all of them got the same response: “This feature is not planned; you should do this server-side instead.”
Well, I’m stuck with Gmail (believe me, I would ditch it in a microsecond if I could), and as of this writing, Gmail’s server-side filters are completely useless. They no longer seem to support any kind of pattern matching, or even negative matching, and Google has obviously stonewalled all complaints about this just like they always do. It’s just not something Gmail users are provided with anymore.
I’m currently receiving a large volume of spam emails (around 2 per hour) which all have a randomized sender and a recipient of the form “[person’s name][random numbers]@aol.com”, where the person’s name is always the same, but the random numbers change every time. (It’s not even close to my email address, but somehow it gets to me anyway). Google’s nerfed spam filters are of no use whatsoever, since they can only match the entire contents of fields to static strings, with no substring matching at all. Thunderbird’s reasonably good filtering system can match these messages just fine, but of course it only works when Thunderbird is running on one of my desktop machines, and like most people, I don’t usually leave those running 24/7. There is one device that I do usually leave running 24/7, though: my smartphone, running K9, which vibrates through the night as these spam messages come in while none of my computers running Thunderbird are awake to catch them.
The stated rationale for not including spam filters in K9 is that doing it client-side means that the device has to be connected in order to filter messages, which is bad, so we might as well not bother. I’m abundantly aware of how much of a problem this is, since it’s the entire reason why I can’t keep these spam emails from bugging me, but if it could be done by my one always-on device, instead of my three usually-off ones, it would at least be good enough.
I don’t think we’re ever going to see any help from Google, and I cannot switch away from Gmail without also switching away from my current career, so server-side filtering is as good as lost to me and everyone else in a similar situation (which can’t be a small number, given Google’s overwhelming market dominance).
As I see it, I don’t have many options besides coming here to beg for message filters again. K9 is the only email app that my phone can run and I can tolerate, and none of the other entities involved in this appear to be willing to listen. I know that K9 has limited development resources and that it will take time to implement this, but it would really help to see any sign that it’s being considered. So far, all I’ve seen on this forum is other people in my situation being told to get lost and find some other way to block spam, but I’m here to say that there simply isn’t. I’ve tried.
All this being said, I want to make it clear that I’m immensely grateful for K9’s existence and all the work you put into it. Without it, my online life would be dramatically more miserable than it already is, and it’s truly amazing that a community effort like this can have that much impact. Seriously, good work. Even regardless of your decision on message filtering, I’d say I owe you a donation.