My pico ist unable to activate the bootloader to upgrade the firmware 1.93 to 1.99

If the messages you are referring to are in the left hand pane of the IDE, you are able to mouse rollover and highlight that section, Ctrl+A Ctrl+C to copy to the clipboard,

Just so you know, just clicking and dragging to highlight text in the IDE automatically copies it to the clipboard. Ctrl-C issues a 'break' command to the Espruino interpreter which will break out of the currently running code.

If I press the button on the top of the pcb during plug in, nothing happens. The blinking led not changing. It's the same, when I insert the pico without pressing a button.

So: You get the red LED flashing once when you plug the board in, but pressing the button while plugging it in makes absolutely no difference at all? Still just one red flash?

Are you sure that the button really is being held down? It seems amazingly unlikely but I guess it's possible that the button is broken.

You could try plugging in while shorting across the button:

  _________
A<|   ___   |>C
  |  |___|  |
B<|_________|>D

So either shorting A and B, or C and D.