Or how opening a Microsoft Office document, then accidentally saving it, leaves fingerprints identifying you behind, as repeatedly happened with the Wikileaks election leaks. To fix this yellow-dot problem, use a black-and-white printer, black-and-white scanner, or convert to black-and-white with an image editor.
Copiers/printers have two features put in there by the government to be evil to you.
The picture at the top of the page shows just a tiny bit of medicinal bottle diversity which is frankly staggering in depth and variety as virtually any shape imaginable was used at some point.
The bottle pictured to the left is a mid-19th century medicine with a general shape (rectangular with indented panels) that was used for tens of thousands of different medicinal products from the mid-19th century until at least the Depression in the 20th century.
The first is that scanners/copiers (when using scanner feature) recognize a barely visible pattern on currency, so that they can't be used to counterfeit money, as shown on this below: The second is that when they print things out, they includes these invisible dots, so documents can be tracked.
In other words, those dots on bills prevent them from being scanned in, and the dots produced by printers help the government track what was printed out.
Later, the arrest warrant request for an NSA contractor named "Reality Winner" was published, showing how they tracked her down because she had printed out the documents and sent them to The Intercept.
Though intimidating in its immense diversity there are some useful trends in shapes that mark a bottle as very likely to have been used primarily or originally as a container for some type of medicinal product.
The breadth of variety within the medicinal bottle category is indicated by Fike (1987) dividing his classic book (The Bottle Book: A Comprehensive Guide to Historic, Embossed Medicine Bottles) into over 40 different "product" chapters, ranging from "bitters" to "cures" to "purifiers" and many more.
You should see a roughly rectangular pattern checkerboard in the whitespace.
The document leaked by the Intercept was from a printer with model number 54, serial number 29535218. The NSA almost certainly has a record of who used the printer at that time.