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I upgraded as per the guide to the latest version (S.O. Debian12 and php 8.0), but now when I run a survey I see parts of the php script code within the survey. There is nothing in the logs, what's the problem?

You did not answer the basic questions that appear when you create a new post.

What version are you using. And no, "the latest version" is not enough. Because what was the latest version when you did the upgrade might not be the latest version now. Also, currently Limesurvey offers 3 valid branches (LS 3.x, LS5.x and LS6.x). This means there are 3 "latest versions" of Limesurvey at any given time.

So, let us know from which version / branch you upgraded and to which version / branch you upgraded.

Also, it might make sense to post a screenshot of the actual problem.

The link will not be online for a long time:
limesurvey-test.doit.systems/index.php/713291?lang=it
I attach photos of the problem 

I also activated ComfortUpdate which ran the process but when I open the survey it still has problems and displays the php code in the image.  Furthermore, the icons for selecting the image are not visible.

Link: limesurvey-test.doit.systems/index.php/713291?lang=it

 How to solve?
 Thank you.
 

dany85free wrote:

 it still has problems and displays the php code in the image.  Furthermore, the icons for selecting the image are not visible.
 

I don't see PHP code only HTML Tags.

How did you upgrade from LS 5 to LS6 in the first place? What did you exactly?

When you create a fresh survey with a shipped, unmodified theme, do you see the same issues? Or are other survey workings.

The faulty survey tries to get data with a URL with <h2 style= at the end.

GET
limesurvey-test.SNIPHOST/index.php/

[HTTP/1.1 404 Not Found 533ms]

I would recommend to install a fresh LS6 and import theme and survey. If the survey showing the same issues, you have to redo the theme.
If it is working your upgrade process was not complete.

 

The upgrade Is fine by ComfortUpdate

It seems that you are using the multiple choice image-select question theme.

What did you place in the sub-question text? It looks like there is invalid HTML there.