Create Issue pop-up comes up blank

[Spiffu]

Hi, I'm trying to resolve a problem involving the Create Issue function.

This is the server setup
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Testlink 1.9.5
XML-RPC Bugzilla bug tracker integration (using bugzilla 4.2.1)
Linux O/S Debian 3.2.46-1 x86_64
Apache 2.2.22-13 amd64
PHP5 5.4.4-14+deb7u2
---------------------
The bug is as follows:
I've created a test specification, a build, and test plan.

I added the test cases to be executed in the test plan. I failed one of the test cases, and then clicked on the Create Issue icon. This generated the pop-up window, but there was no content inside. The url the pop-up window was trying to reach was this:

//url/tl/lib/execute/bugAdd.php?user_action=create&tcversion_id=20&tproject_id=1&exec_id=1

Note: The Link Existing Issue button works fine, in that it generates a working pop-up and I can link a Bugzilla ticket from our site using my account. So I don't believe this is an issue of Bugzilla/Testlink connectivity.

I am trying to figure out why the Create Issue doesn't show any content. If anyone can help out, I'd be very grateful.

Thanks

[fman]

1.9.5 is too old, you need to check mantis.testlink.org to understand if this is a reported and solved issue.
Anyway you have to upgrade because support is dropped for versions < 1.9.7

I'm not able to access to the URL, can you fix it ?

[Spiffu]

I posted the html of what the pop-up page was generating as a reference. The page is an internal website, it cannot be visited from the outside.

[fman]

Next time please post an image, to allow better understanding.
Please proceed with upgrade