The issue detailed in this thread is still happening, however the solution presented is no longer relevant since the Google Cast extension has been discontinued. Is there a way to keep using Chromecast from Chromium, or is it no longer possible at all?
(As a side note, I would like to mention that I initially wanted to participate in the initial thread so as to avoid duplicate threads but I could neither add comment (50+ reputation points required) nor an answer (10+ reputation points required) and therefore I was advised to open a new thread instead.)
cast...menu, at least for version Version 63.0.3239.84 (Official Build) Built on Ubuntu , running on Ubuntu 16.04 (64-bit), and it's working with my tv. – pim Apr 16 '18 at 16:06