I did some very in-depth research into the lapdock ecosystem a few months ago on the Samsung Dex subreddit, and found some accessories that may be of interest to Librem 5 convergence users:
https://tenonedesign.com/mountie.phphttps://tenonedesign.com/mountieplus.phphttps://phoneside.com/en/products/phoneside-one
Between these three products, I am most likely to tentatively recommend the Phoneside One, since it grasps the form factor of a smartphone from the sides similar to a vice grip, instead of directly clamping onto the phone display like the other listed products, or using adhesive on a magnetic plate attached to the Librem 5 as a mount as the Lapdock Kit provides. I could have simply created a topic on the Purism community forums about this, but I decided to use this opportunity to test whether HyperKitty supports lists within email bodies and to learn more about how GNU Mailman 3 works.
Frank