Found one more reason to drop frames support.
demographics.php is the only way to navigate to all data related to this patient - may be selected from calendar. All links to are then visible but unresponsive until everything is loaded. In addition to large number of ajax calls for patient data, this process also includes display of encounters. If your practice has patients with several years of visits, it is now starting to take 30-45 seconds and beyond to get your clicks accepted by the browser.
In frames era that was tolerable since each frame responds when ready in its container. Encounters frame was immediately visible and needed to be updated. In case of tabs interface, the user ends up paying the penalty of waiting till encounter tab is populated in the background and in more than 90% of times does not use that list anyway.
Since we changed the navigation as part of Demographics v5+ : Title block (0) , the loading of enc tab is now discontinued. If required, users can now choose list or specific encounter from title block. This has cut the wait in half.