I suggest implementing a "mark as spam" button near each post on the forum. After a post has gathered x spam marks, someone on the team should get an email, suggesting the deletion of said post. The post itself might also be added to the email, in order to simplify the decision.
https://trisquel.info/fr/users/fujia644713 has just created an account to post advertisement on wedding dresses.
https://trisquel.info/en/users/drclintcornellpac
https://trisquel.info/en/users/ihanterro
https://trisquel.info/fr/users/belucky110 posted three times the same advertisement on the French-speaking forum (hidden in some English text). Only those.
https://trisquel.info/es/users/cephasjimes7
https://trisquel.info/es/forum/buy-quality-real-and-fake-passports-driving-licenses-identity-cards-zezethumatigmailcom
https://trisquel.info/en/users/mchlmldn
Not a spammer but someone (mauldin) who wants his account and posts deleted: https://trisquel.info/fr/forum/i-need-my-forum-posting-deleted-and-account
I unpublished the thread and warned the author via email
this thread advocates proprietary software
https://trisquel.info/en/forum/limited-time-offer-get-theme-hospital-free-origin
https://trisquel.info/en/forum/laws-approving-cannabis-decriminalization-benefit-states (notice the spam link to a cash loan website and the comment from ssdclickofdeath for more info on why it's probably spam)
https://trisquel.info/en/users/sarahtaylorusa
https://trisquel.info/fr/users/sanjitasai has just registered to post that advertisement: https://trisquel.info/fr/forum/automatically-installed-javascript-must-die#comment-60707
https://trisquel.info/en/users/sweeney123
https://trisquel.info/fr/users/wherenizai posted https://trisquel.info/fr/forum/ten-years-may-be-toms
https://trisquel.info/fr/users/keithscott signed in 45 minutes ago to only "suggest to use Compare Panda website where you can find millions of books with discounted rates from amazon and amazon marketplace": https://trisquel.info/fr/forum/where-do-you-buy-printed-books-online#comment-58483
An old one: https://trisquel.info/en/users/shagydeep
From this thread: https://trisquel.info/en/forum/how-transfer-gpg-key-another-computer
https://trisquel.info/fr/users/sandralyn0216 only sent:
https://trisquel.info/en/users/technojohn
https://trisquel.info/en/users/velvetarts
https://trisquel.info/en/users/alexisfick
https://trisquel.info/en/users/novanjlon
https://trisquel.info/en/users/rhondafournier
https://trisquel.info/en/users/alax-g
https://trisquel.info/fr/users/shayla-davis registered to post that advertisement: https://trisquel.info/fr/forum/gnu-cash-keyboard-problem-trisquel-7#comment-55855
https://trisquel.info/en/users/bit-road
Wow, that thread was a big spam magnet.
depikarani654
http://trisquel.info/en/forum/anyone-got-touchpad-running-chromebook-trisquel-6#comment-55525
sigh...
https://trisquel.info/en/users/lizaangle7773 has just registered to post that advertisement: https://trisquel.info/en/forum/anyone-got-touchpad-running-chromebook-trisquel-6#comment-55523
https://trisquel.info/en/users/somaakter759
https://trisquel.info/en/users/steve002 makes advertisement: https://trisquel.info/en/forum/removing-services-not-needed-need-advice#comment-55340
https://trisquel.info/en/users/miz454 registered to post that advertisement: https://trisquel.info/en/forum/anyone-else-frustrated-lack-webm-content-and-webm-quality-youtube#comment-54571
https://trisquel.info/en/users/estellemayon3
https://trisquel.info/en/users/madrepadre
https://trisquel.info/en/users/handy-john
https://trisquel.info/en/users/callumj85
https://trisquel.info/en/users/bhai
https://trisquel.info/fr/users/anikaakter754 posts advertisement: https://trisquel.info/fr/forum/anyone-got-touchpad-running-chromebook-trisquel-6#comment-53860
https://trisquel.info/en/users/rocio10
https://trisquel.info/en/users/pknation