Description of problem:
When user opens process preview diagram in Process Instances perspective (click row for some proc instance > In details panel select Options > Process model), the process model is only loaded for the first time.
The issue is that after this the preview is not loaded anymore and more importantly it's not longer possible to open designer in Authoring Perspective. See video illustrating the issue with 6.2.2 patch.

This bug was recently reported for 6.4.x community branch (see jira https://issues.jboss.org/browse/JBPM-4944) and now it also happens for 6.2.x patch.

The bug happens both in firefox and in chrome.

Version-Release number of selected component (if applicable):
BPM Suite 6.2.2 patch

How reproducible:
Always

Steps to Reproduce:
1. Create some process model, build & deploy the project, start an instance of the process in Process Definitions perspective.
2. Go to process instances perspective, click the row for running instance
3. In Details panel select Options > Process Model
4. Modal dialog with process preview is displayed. Close the modal.
5. Repeat step 3 for the 2nd time

Actual results:
The process preview is not loaded. After that when I navigate to Authoring perpsective no other process can be opened in designer.

Expected results:
It should be possbible to open process preview modal and see the process multiple times (e.g. when checking state of more than 1 process)