18.104.22.168 is what I have. Pretty sure the differences are tiny.
Firefox/PaleMoon is mentioned in Tools->Settings->Browser.
And I had no problem putting it on Pale Moon. You have to use the Legacy .xpi which you download to your disk/desktop whatever and is on the Linkman Firefox extension page. Then you pick it up with the button in the Pale Moon Extension page that loads an extension from a file. That is what worked for me on Pale Moon, also Waterforx and Cyberfox, I think. (Lenovo SFF with little on it, so I loaded about 12 browsers for fun.) It is all the same extension. It would work for Firefox 56 but why bother with Pale Moon handy. You can identify the browser by using the Tools-Settings-Browser User Defined. (Or default is good too, for calling.) That is helpful for loading a page from Linkman to the browser, where you have various choices even at the time of loading.
If you use the Quantum .xpi then it will say the file is corrupted and the extension will not load.
The extension will always communicate with the Linkman Drop Basket, just remember that if it is squirrelly you probably initiate the ADD/EDIT from the browser side.
And sometimes you change 80 to 81, port, but on my latest use of a Windows 7 it was not clashing with Skype, dunno why, so I left everything at port 80 for now.
I do go in and out of Pale Moon, Firefox (Quantum and Quantum ESR) and Chrome (regular and Canary). I use Opera for some oddball sign-ons as well, it is my back-door browser. And use the others more on a whim.