Dashed line doesn't print (TikZ)

My job involves emailing a lot of PDFs to people to print out, so the "update your printer driver" solution doesn't really help me.

But what I've founded is that while dotted or dashed lines refuse to print, dotted or dashed sine waves show up fine, even if the amplitude is zero. So I put the following at the top of my document:

\usetikzlibrary{snakes}
\tikzstyle{printersafe}=[snake=snake,segment amplitude=0 pt]

Then add [printersafe] as a style to every dotted line in the code, e.g.:

\draw [densely dotted,printersafe] (0,-6) -- (10,-6);

These lines show up fine, even when printed by TAs who experience the original issue.

So, I recently ran into this problem and found @Jonah's solution. Thing is, it doesn't really work with how tikz behaves now, so I made the following changes which should make this code more up-to-date:

\usetikzlibrary{decorations.pathmorphing}
\tikzstyle{printersafe}=[decoration={snake,amplitude=0pt}]

With this you can also use printersafe within tikz-cd environments. Hope this helps!