I have a file named "out" (from ii) that I want to view.  Of course, it can 
grow while I am viewing it.  I can view it with "tail -f out" or "less +F out", 
both of which work.  I also want to apply some processing in a pipeline, 
something like "tail -f out | tr a A | less" but that does not work.  The less 
command ignores my keystrokes (unless I hit Ctrl-C, but that kills tail and 
tr).  The "tr a A" command is arbitrary; you can substitute whatever processing 
you want, even just cat.

This command "tail -f out | tr a A" is functional and has no bugs, but it 
doesn't let me use the power of less, which I crave.

This command "tail out | tr a A | less" is functional and has no bugs, but it 
doesn't let me see newly appended lines.

Can I use the power of the Unix pipeline to do text processing and the power of 
less for excellent paging and still be able to see new lines as they are 
appended?  Why doesn't or can't less continue to monitor stdin from the 
pipeline and respond to my keystrokes from the tty?

I am using Debian 11 in case it matters, with fish.  But I am happy to try 
other shells.  In fact I already have and that doesn't seem to help.  I have 
also tried more, most, nano -, and vi -, instead of less, to no avail.

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