When I do "/fill x1 y1 z1 x2 y2 z2 magenta_stained_glass_pane replace (any block)" and the blocks I'm replacing happen to be adjacent to other blocks, when the glass panes clone in they are not affected by adjacent blocks. They stay in their default "stick" form. This doesn't happen when I place the blocks down, only with the "replace" function of the "/fill" command as far as I know.