I thought I’d update this thread as I believe lack of console view remains as one of the blockers to Modern UI adoption by some.
My new preferred solution to the viewing of Console in Modern UI actually has advantages, imho, over the console window in Classic UI, and it is relatively simple, although depending on your OS you may require a third party tool to make it simple. It also works best if you have dual monitors so the console is on the other monitor.
In Unix (sorry, showing my age 
)… Linux! you have the tail command to continually show the latest lines added to the end of a text file.
In Windows you can install a third party tool (my choice is the free version of “BareTail” which has a very small footprint).
In Modern UI, open the menu item “Show KNIME log in File Explorer”
then drop the knime.log file onto BareTail or otherwise open it with your “Tail” utility of choice. Make sure tail is set to “follow tail” (the -f switch in linux if my memory serves).
You could, if you wish, set up a shortcut on your desktop to open the logfile in “tail”.
The advantage over the classic console viewer is that you get to see the date/timestamps of the log entries, and additionally viewing the console also isn’t consuming any of KNIME’s processing time.