Generally this add-on is exactly what I was looking for.
Right click to open link in new tab.
Holding right click for 0,5 sec. to open context menu.
Brilliant! Nothing more to add.
...but I've got one BUT
I also use "mouse gesture" app.
I know that propanly the better choice is to pick up some firefox's add-on like e.g. Firegestures, but I prefer external app witch called StrokeIt and allow to uses mouse gestures for all Windows apps, not only for firefox browser.
For some reason, when I use StrokeIt, after clicking on link and holding mouse button longer than defined timeout (500 ms), context menu not want to show up :(
Everything is ok when I turn off StrokeIt.
To be honest I've to add that in conjunction with Firegestures that problem doesn't appear.
So you propably give me advice to get rid of StrokeIt and stick with Firegestures.
I also add that both StrokeIt and Firegestures I use with right mouse button.
So, may I ask you to check why your add-on doesn't work properly with StrokeIt?
I would be really thankful.
Thank you for your quick answer.