Question: I was looking to download kdiff for windows from
<https://download.kde.org/stable/kdiff3/>

and I noticed the latest package is
kdiff3-1.8.5-windows-64-cl.exe

while the next-latest is
kdiff3-1.8.4-windows-64.exe

Does the -cl signify anything like a library I need or stability or ???

There is 0 documentation that I can find on how to download and install anything later than 0.9.98.
Couldn't find any clue on the project site
<https://invent.kde.org/sdk/kdiff3>

about the -cl and I couldnt figure out how to ask there ...

Loading up a new computer and reluctant to add something that seems a little like it might have special requirements or caveats.

thanks!

Answer: 
It was built using the MSVC command line compiler (cl.exe) that comes with Visual Studio.
See: <https://learn.microsoft.com/en-us/cpp/build/reference/compiler-options?view=msvc-160>
I can't say what the `-cl` stands for, but it has been a suffix before, for example for version 1.8.2. I'm currently running 1.8.5 (from that location, the one with the `-cl` suffix) and it works fine.