Class 'phpQuery' not found

Hi
This application looks great and whilst testing the free version I have noticed impressive speed increases. However, for many blog and article pages at our site we get blank screens with the error "Class 'phpQuery' not found".
To fix this we have to downgrade to PHP version 5 from 7.2, which is very frustrating.
So, before I go and look for an alternative application is this a known issue? What do I have to fix to get it working with PHP version 7.2 / 7.3?
Any advice would be appreciated.

Mobile Joomla! doesn't use phpQuery class. Do you have file name and line number in the error message text?

Thanks for looking.
This is the debug report...

Class 'phpQuery' not found

Call stack
# Function Location
1 JApplicationCms->execute() /home/juicebik/staging/1/index.php:49
2 JApplicationSite->doExecute() /home/juicebik/staging/1/libraries/cms/application/cms.php:261
3 JApplicationSite->dispatch() /home/juicebik/staging/1/libraries/cms/application/site.php:230
4 JComponentHelper::renderComponent() /home/juicebik/staging/1/libraries/cms/application/site.php:191
5 JComponentHelper::executeComponent() /home/juicebik/staging/1/libraries/cms/component/helper.php:380
6 require_once() /home/juicebik/staging/1/libraries/cms/component/helper.php:405
7 JControllerLegacy->execute() /home/juicebik/staging/1/components/com_content/content.php:38
8 ContentController->display() /home/juicebik/staging/1/libraries/legacy/controller/legacy.php:702
9 JControllerLegacy->display() /home/juicebik/staging/1/components/com_content/controller.php:113
10 ContentViewCategory->display() /home/juicebik/staging/1/libraries/legacy/controller/legacy.php:664
11 JViewCategory->display() /home/juicebik/staging/1/components/com_content/views/category/view.html.php:258
12 JViewLegacy->display() /home/juicebik/staging/1/libraries/legacy/view/category.php:233
13 JViewLegacy->loadTemplate() /home/juicebik/staging/1/libraries/legacy/view/legacy.php:216
14 include() /home/juicebik/staging/1/libraries/legacy/view/legacy.php:677
15 JViewLegacy->loadTemplate() /home/juicebik/staging/1/templates/juicy/html/com_content/category/blog.php:61
16 include() /home/juicebik/staging/1/libraries/legacy/view/legacy.php:677

Perhaps upgrading Joomla from 3.6.5 would update the libraries, but that does cause other problems in other components...

phpQuery is not part of Joomla! too, so unlikely updating 3.6 to 3.9 will solve the problem. The line

16 include() /home/juicebik/staging/1/libraries/legacy/view/legacy.php:677

is just running of the template, so most likely there should be either extra lines after "16 include()", or there should be a filename:linenumber info somewhere at the end of error message (but before call stack).

Well, after a re-install and revert to Joomla 3.6.5 all is up and running on elegance template with PHP 7.2 working. Speed is excellent improvement, so now I am happy!
Just one thing you may help with: the menu for a section (see www.juicybike.co.uk menu item "Why e-bike" will not expand. Not sure why? Otherwise, impressed!

As to "Why e-bike", this menu item is of separator type, and that's why it is rendered as a separator in mobile template. I'll try to make separators expandable as well in the next Elegance release, at first thought there should be no problem with implementation of such a fix.

@BobWales Hmm, no, it's not a separator (separator items are supported properly in Mobile_Elegance template that you use).

Do you use latest Mobile Joomla (2.1.31) and Mobile_Elegance (2.0.21) versions?

Could you send me (denis​@​mobilejoomla.com) screenshot of those menu items from backend (with its types below title)?