atril | A document viewer for MATE | Document Editor library

gnuplot's original latex terminal, the one you get by saying "set term latex", is horrible by modern standards. Use one of the more recent ones. My favorite is the tikz terminal:

gnuplot>

Another nice change can be observed in the document shared by the OP:

What we see here indeed is the result of OCR. But it's not some ocr happening behind the scene in the viewer, OCR has already happened before and the results have been integrated into the PDF.

The PDF page actually contains a scanned image upon which invisible text is drawn.

As long as nothing is selected, Atril shows exactly that, you only see the scanned image. As soon as you start selecting text, though, it appears to cover the marked area in blue and display the marked (formerly invisible) text in white upon it.

In situations, therefore, in which the invisible text is not added exactly above the corresponding letters in the image, this might result in funny gaps like the one in the OP's screenshot after "multidimensional". In case of errors in the OCR output, one sees the erroneous data like in my screenshots.

Other PDF viewer often merely mark the text by applying some effect to the text area, e.g. inverting colors or overlaying a semi-transparent color.

It might be considered an advantage of the Atril approach that already in the selection process one sees the exact text one is selecting and probably eventually going to copy.

As mentioned above, the PDF page actually contains a scanned image upon which invisible text is drawn.

In the page content stream the corresponding instructions look like this:

It looks as though I've found a partial answer to my own question. It's imperfect for various reasons:

• It probably depends on startxwin already having been launched elsewhere as a background process.

• The applications are slow to launch; there's a delay of a few seconds.

• Terminal windows which the user cannot interact with (presumably the shells which act as parent process for the GUI applications) appear alongside the application windows.

But it will probably be enough to be getting on with. Assuming pluma to be our application, here is the shortcut that successfully launches it: