It appears some are having issues with the update to plug in 1.8 for tethering Fujifilm cameras in Lightroom. At this time there is some mixed information and some are claiming that reinstalling their 1.7.0 plugin is fixing the error. Fujifilm has been notified and Adobe is working on a solution. For right now if your tethering is working then you probably do not want to mess with it and if you are having issues you can find the 1.7 links below.
FUJIFILM Tether Shooting Plug-in PRO 1.7.0:
FUJIFILM Tether Shooting Plug-in 1.7.0
Relead Groups
Fujifilm GFX Owners Group
Fujifilm X-H Owners Group
Fujifilm X-T Owners Group