bahaviour::modal not found - what to do?

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bahaviour::modal not found - what to do?

Post by amcgibbon » Sat Oct 23, 2021 4:21 pm

I have this exact same problem at the moment. I am getting the error:

behavior::modal not found.

Can anyone recommend a way to track down this problem. I'm not an experienced coder. I'm not even sure what information to give to help resolve this.

Many thanks in advance.
Last edited by toivo on Sat Oct 23, 2021 7:36 pm, edited 1 time in total.
Reason: mod note: split from someone else's topic - please create your own topics in the future!

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Per Yngve Berg
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Re: bahaviour::modal not found - what to do?

Post by Per Yngve Berg » Sat Oct 23, 2021 8:30 pm

Enable debug and get the stack trace.

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Re: behaviour::modal not found in J! 4

Post by sozzled » Sun Oct 24, 2021 6:21 am

I think there will be a lot of people who will struggle with this issue.

Let's start with what we know. We know that messages that include the words "behavior.something" are related to Mootools (see We also know from discussions on GitHub that one of the reasons the Weblinks extension was one of the last "official" extensions released for J! 4 is because it relied on the Mootools-based behavior.modal method.

In addressing another question related to Mootools, I think we may have uncovered a potential problem area for J! 4. I don't think the error message mentioned by the OP comes from the J! 4 core CMS—but I could be mistaken and if that were the case it should be reported to the developers. It's more likely that the error message is generated by a J! 3.x (or even J! 2.5) extension installed on the OP's website. As @Per says, enable J! debug mode, get the stack trace, and see the source of the problem.
“If you think I’m wrong then say, ‘I think you’re wrong.’ If you say ‘You’re wrong!’, how do you know?” :)

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