Error on Cannot read properties of null (reading insertBefore)

4
I got the error when I tried to do the advanced learning path. I usually use Mendix 9.6.10, but I want to learn the advanced part, so I downloaded the 8.12.0 version for practice.  But it shows this error now,    Cannot read properties of null (reading 'insertBefore') TypeError: Cannot read properties of null (reading 'insertBefore')     at Function.p.injectUrl (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:13361)     at Je (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:11685)     at c (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:466)     at http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:5196     at qe (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:9756)     at he (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:5181)     at pe (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:5534)     at p (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:5:651)     at U (http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:80:244137)     at http://localhost:8080/mxclientsystem/mxui/mxui.js?637867572174395001:80:245668
asked
10 answers
14

Dear Mendix community,

 

Are there any plans for Mendix to fix the problem above? We cannot expect all our production users to disable their extensions when they use our website. We build websites for all types of users, even for other FrontEnd developers. They fairly often have tools like React Developer Tools and others installed. We risk losing market because of this problem and we don’t see any option to fix this ourselves. Please increase the urgency on this problem and give us an indication that this problem is being recognized and in process of being resolved.

 

Thanks for your understanding.

 

Kind regards,

Jochem Geussens

answered
9

Hi Man.

Which browser are you using? We found that some Chrome extensions are interfering with the Mendix client and cause this error. Try deactivating all extensions and test without them. Then step-by-step activate them again to identify the once causing this issue for you.

answered
5

Since yesterday we get this error alot too when trying to login.. With us it's the chrome extension LastPass, the js file Onloadwff.js (and possibly the widget 2FA).

 

Are more mendix users hit by this?

answered
4

Hello community members, we filed a support ticket with Mendix and it appears they are under the impression that this is an isolated issue since there are no other official tickets filed with the same problem description. Please if you are affected by this issue, file a Mendix Support ticket in order to get this properly prioritized.

answered
3

I've just updated my Dashlane extension to 6.2311.3 and now I can access Mendix apps normally again.

answered
2

Several members of my time have recently started experiencing this error when accessing https://sprintr.home.mendix.com from Chrome or Edge browsers. Some of us are on macOS while others on Windows.

answered
1

Same problem here for multiple users of ours. They get it when they go the login page, not even logged in. Very annoying and hard to tell them how to solve this.

 

Will issue a support ticket about this. Anyone an idea about a workaround?

answered
1

While disabling extensions could help, the best way to resolve it would be to upgrade to Studio Pro 9.24.4 (or higher) (or Mx10). From the release notes:

  • We fixed an issue where Chrome extensions crashed the client. (Tickets 180229, 180230, 180385, 180405, 180450, 180472, 183144)
answered
0

It looks like you are trying to read a attribute from an empty entity, to fix this you should first check if the object exist ($Entity != empty) and then read the value of the attribute. If this doesn't work could you please add some screenshots from the code where it goes wrong?

answered
0

I've encountered this exact issue too when running an instance of Mendix on my local machine. It wouldn't render past the log-in screen at all with the console throwing an exception as mentioned here.

 

Turned off the Lastpass-extension and this immediatly solved the issue.

 

Someone mentioned that updating to the latest Studio Pro-version would resolve it but that is not the case for me as I'm running it with version 10.17.0.

 

So for me this works, if anyone else encounters this issue again then I recommend playing with your browser extensions.

answered