On the forums I moderate many use the captcha for registering new users only, which this forum has for a while now, maybe since it started.
Why expand it existing posting members in good standing if it never stopped spam in the first place?
I get complaints regularly with users unable to get it to work with their browsers for one reason or another.
@JWLV I sent you a PM with Mods that have proven to work for spam please consider installing them and removing the captcha.
These mods will not interfere with members in good standing and auto boot mining bots and spammers alike.
If you need help installing or setting them up I'd be happy to help.