Based on my fidling in How to use Joomla security in own php code - Joomla 6 update i decided to try and cretae a new component 'com_wrapperid' based on the standard Joomla component 'com_wrapper'. Purpose is to be able to install it in parallel without need for overides.
Searching the net I found this very usefull article by Peter Martin: Using Joomla Components - Thx for that one! - and even a suggestion to use 'com_wrapper' as example...
However - the recipe left out a few important mentions!
The structure needed to .zip a component which installs without errors - when copying com_wrapper - must include the following:
as opposed to 
and a few of those are NOT included when you copy 'com_wrapper' from an active Joomla site!
Took a while to compile - and for your information - you need to copy this:
- com_wrapper from /administrator/components/ - this one is the 'root' structure
- com _wrapper.ini from /administrator/language/en-GB/
- com_wrapper.sys.ini from /administrator/language/en-GB/
- com_wrapper from /components/ - elements from this must be copied into the structure created in step 1
- com _wrapper.ini from /language/en-GB/ - not used above. Probably to ./site/language/en-GB - to be tested
- iframe-* from /media/com_wrapper/js/
When all is collected take care to rename 'wrapper' to you selected name absolutely everywhere!!!!
And then modify ./tmpl/your-name/default.php - to what you need it to do! For me it includes
and
That is all!
the module
To Joomla wrapper there is a module as well - mod_wrapper.
I haven't tested - but a little digging suggests that the whole content of '/modules/mod_wrapper ' should probably be copied to ./modules/* - and modified according to above notes.
WIll try that out later....