I see that this is related to the output of the command, so apologies in advance for hijacking the thread, but I have the same error message in my NGINX error log as you and this is the only result in the Matomo forums I could find:
2023/09/01 06:40:38 [error] 73575#73575: *383089 FastCGI sent in stderr: "PHP message: [matomo1.domain.com] Error in Matomo (tracker): Request was meant for a plugin which is no longer activated. Request needs to be ignored" while reading response header from upstream, client: 192.168.0.174, server: matomo1.domain.com, request: "POST /matomo.php?fa_vid=JcBpnl&fa_id=request-form&fa_fv=1&ca=1&idsite=1&rec=1&r=811357&h=2&m=40&s=35&url=https%3A%2F%2Fwww.example.com%2Fen%2Fproduct%2F23444%2F&urlref=https%3A%2F%2Fwww.example.com%2Fen%2Fproduct%2F23444%2F&_id=ffa359d0970446fd&_idn=0&send_image=0&_refts=0&pdf=1&qt=0&realp=0&wma=0&fla=0&java=0&ag=0&cookie=1&res=1430x1300&pf_net=0&pf_srv=559&pf_tfr=385&pf_dm1=1993&pf_dm2=67&pf_onl=7&pv_id=LcPIne&uadata=%7B%7D HTTP/1.1", upstream: "fastcgi://unix:/run/php/php8.2-fpm.sock:", host: "matomo1.domain.com", referrer: "https://www.example.com/en/product/23444/"
I am referring to the Request was meant for a plugin which is no longer activated bit. My only three inactive plug-ins are:
The only plug-in I installed myself was SecurityInfo (v4.0.2).
Anyone knows why this is happening? Should I be worried? I could only find this post in the forums regarding this error.
In this case, the problem is not similar to the other one… Then next time, in order to have one subject per topic, please open another topic when there is no common point with the current topic.
For your specific problem, I think you have to update your matomo.js file or mtm container in order to stop tracking forms (I think this is the plugin that you disabled)…