Hy, Are you asking for a line tool? If so then pixelorama already has one (from v0.9 onward) where you can simply left click and draw a line plus line tool comes with more options like displase origin, symmetric drawing etc...
No I am asking for an option in which if we like select or paint a pixel then go somewhere else in the canvas & then click while holding shift, there will be a straight line made between the pixels. if there is already an option like this, please let me know.