Don't know if it is possible to add something for rotating and zooming on pictures / attachments ?

I have solved these problems for myself via browser addons.

I use google chrome so my 2 main extensions are;
Stylish (https://chrome.google.com/webstore/detail/stylish/fjnbnpbmkenffdnngjfgmeleoegfcffe)
Flip This (https://chrome.google.com/webstore/detail/flip-this/donljlliiecjcagcenoeohjmabfegkph)

I wish there were options for this kinda stuff native to the forum software but until then...

...I have solved these problems for myself via browser addons.



Same here.
I use Firefox ImgViewerPlus (https://addons.mozilla.org/en-US/firefox/addon/imgviewerplus/?src=search).