Modifying HTTrack's Source Code to Break Through Its Limits (Bypassing 'Too many URLs' error)
Hello, I'm incompetent.
This is something I did yesterday, but my memory is fading, so I'll just write it down casually.
Get the source code with git clone
git clone https://github.com/xroche/httrack.git
Next, find the string "Too many URLs" in the source code.
grep -r “Too many URLs” httrack/*
This will show many results, but I found this file:

It seems to be described in httrack/src/htslib.c.
So, I haven't tried `*` or anything, but I casually put in a number with an almost infinite number of digits.
It seems there are also speed limits, but if people start saving without regard for speed, it would be troublesome, so I'll only post a hint image and won't give out the details.

Build and install
./configure --prefix=$HOME/usr && make -j8 && make install
Then, if `which httrack` doesn't point to the installation directory, rename or delete it, then create a symbolic link to the newly installed one at the `which` location, in my case, like this:
sudo ln -s $HOME/usr/bin/httrack /usr/bin/httrack
With this, the HTTrack Mod is complete.
Apparently, this 'Too many URLs' message is a remnant of old software created around the year 2000. If I were to completely remove it from the source code, it would be a bit sad, so I also feel like it should remain as it is.
That's all for now.
I look forward to your continued support.