Coding of screen content includes identifying corresponding areas in one or more previously coded frames to code unchanged areas in current frames. An unchanged area in a current frame is coded by copying a corresponding area from a previously coded frame or several previously coded frames. Usage of a copy mode to be applied to the unchanged areas is signaled in an encoding bitstream. The copy mode can be signaled for each unchanged area or a single copy mode is signaled for a group of unchanged areas. The copy mode can be automatically applied to one or more unchanged areas contiguous to the group of unchanged areas without further signaling the copy mode. Copying the corresponding area from the previously coded frame includes copying palette entries from the previously coded frame. Palette entries copied from the previously coded frame are reordered according to frequency of appearance.