Very inconvenient to read electronic PDF

Hello. It is very inconvenient to read electronic PDF in your program. There is no automatic adjustment of the width of the program window to the width of the monitor, so that exactly half the page is displayed on the screen and you can move it to the second half of the page with the click of a button. Now, if you stretch the page to the full width of the screen, then when scrolling with the PageDown button, you need to look for the place that was at the end of the previous text fragment. I am using a DELL LATITUDE D430 laptop
Screen resolution 1280x800
Screen diagonal 12 … 12.1 "

I experimented with some settings an have to agree you are perfectly right it is not easy to force a half page setting other than use windows snapping to exactly a screen or half width

However I could do as you wish with some adjustments Note ever page size, screen monitor resolution and user is different.

If you accept it is easiest to use a portrait page (in my case A4 but it could have been equally Letter size) then setting the window to full screen makes for a fixed setup, I needed to adjust user
dpi value to suit my specific hardware (and most users would need different to their neighbour)
so I found thatCustomScreenDPI = 141

worked perfectly for me to jump up down exactly 1/2 page using page-up and page-down keys