I'd rather use one filter per email address, not one filter for all email addresses. You can sort filters by using the 'Move Up' and 'Move Down' buttons.

Whether it makes sense to use filters for that purpose is a different story, but you haven't explained what you're trying to achieve in the first place.

I would have thought that one filter for all unnecessary emails is much quicker than repeating the same filter for each subsequent email that one also wants to delete. ---'Move Up' & 'Move Down' is only a manual task, better 'twould be to have an automatic sort. ---Can you offer any advice on the @, i.e. is this symbol necessary when only the domain name is listed? Thanks for quick reply.

Can you please consider clarifying each use of the word "email". I'm struggling to understand whether you mean email message, email account or email address.

I'd collect "bad" senders into their own address book and use a fiter for "is in my address book". Blocking by domain is perhaps better done using the allow/block lists found under Tools|Options.

I believe you'll find that the filters are blind to the @ character.

I wasn't aware that differentiating between "email message, "email account", and "email address" was so important. My query concerns the filtering of "email addresses". In my screen shot of Filter Rules, I have set "Getting New Mail" for "Match any of the following" on "From" | "contains" followed by a list of email addresses. Where several email addresses have the same domain name, I have specified simply the domain name, with the '@' foremost.

Surely, this procedure shown in my screen shot is precisely the same as your suggested collecting of "bad" senders in their own address book? I cannot find Tools|Options under my "Thunderbird 38.6.0".

I don't think using filters to manage spam is a good idea. You are forever playing catch up. Effective spammers don't re-use the same "from:" address indefinitely. However, IMHO adding addresses to an address book is less work than creating additional filter rules. Address Books are designed to be of indefinite size, but a large filter with many lines is less efficient and more work to maintain.

The filters were provided to support management of messages; typically moving messages to appropriate folders, or adding tags to draw emphasis. Whilst they can be used to manage spam, it is not recommended.

I would hope that anyone trying to ask a question would care that what they had written made sense. Text littered with the word "email" isn't helpful, since that's what we're here to talk about.

The outcome of using your filter method and using my address book method may be the same, but since the methods used are different you can hardly say they are "precisely" the same. The devil is in the detail.

And note that starting a line with a space will cause it to appear as one long line in fixed-width font. This is designed to support text that needs to appear verbatim, such as programming code and tabulated data.