On my win 10 32bit system, I either can’t copy anything from serial monitor, or I can only get the first portion. If I get the same serial message on a win 10 64bit system, I can copy the entire serial monitor content. If you have a small laptop running win 10 32bit, can you give it a try? Don’t want to report on github unless I can get multiple people having the same issue.
I can imagine that it won't work, especially if data is generated fast. However:
Which version of the IDE are you using? and can you provide a sample sketch that shows the problem?
If I want to capture all data I use putty.exe (or other real terminal program) that has data capture built in.
It is 1.6.5 r2. Same code works fine on a 64-bit system, same ide version. Data are not too fast. Yes, I can use terminal by br@y++ but the integrated one is a lot more convenient now that is stays open between uploads.