Hi @vol4ikman
A JS script of one of your plugins probably depends on jQuery, but that plugin doesn’t queue jQuery if no other plugins do it. Contact Form 7 loads jQuery, and you have no issues until it’s active.
When you disable CF7, no other plugins call jQuery. And it’s right they don’t queue it if they don’t need it.
When a plugin needs jQuery it should ask something that looks like:
“if jQuery is not loaded, load it. If jQuery is loaded, than do this and that using jQuery.”
One of your plugins is doing this:
“Do this and that using jQuery”. And that’s it, without checking anything, and without calling jQuery before using it. Of course, if nobody loads jQuery, and you use it, you will trigger a JS error.
You should understand what plugin is doing that, and write the authors of that plugin to address this issue.
For detecting the guilty plugin, you can do as follow:
- Rigth-click with your mouse on the homepage
- Click on Ispect
- Click on Console
- Where you see “Uncaught ReferenceError: jQuery is not defined”, you should also see the path of the script that is giving that error. That path should include the folder of the guilty plugin. You will not see it, only if the JS script is inlined.
If it doesn’t help, I suggest you to share the URL of the homepage.
I hope it helps,
Have a great day!
Jose
