[Cin] TODO lines in tex?

For example in Windows.tex I see (in plain text mode) this piece of text-code: begin{figure}[htpb] \centering \begin{minipage}{.49\linewidth} \center{\includegraphics[width=1\linewidth]{window_layout1.png}}\\ a) %TODO High res image replace does this mean we still need better png here? Also, can illustrative pngs be compressed (lossy) with pngquant utility? It makes paletted pngs. Not sure how various pdf viewers will react to that ....