RTL supporting themes and Drupal 8
Last summer I was looking for a free, responsive, Drupal 8 theme, that was guaranteed to support RTL languages (Arabic in this case). With a minimal budget for visual presentation, the selected theme would need to work well and look good with the minimum of tweaking.
After spending some time researching this question I soon realised that the info and documentation supplied with a lot of themes was either vague, or entirely absent, on the issue of RTL support.
Fast forward several months and still a search for "RTL" in actively maintained D8 themes on drupal.org returns just 4 results - two of which are "starters". Whilst there are a few paid-for themes that explicitly support RTL, even these are very few - just a handful for Drupal 8. In fact most of these are really installation profiles that come with lots of functionality pre-prepared, rather than "just" a theme for visual presentation alone. In our experience, these can often introduce more problems than they solve.
In the end we decided to stick with something we knew would "just work" and created a subtheme of Drupal's core Bartik theme and then applied some minimal stylistic changes to bend it towards the desired outcome. The result can be seen here: qurnainthesky.org and more info about this project can be found here: <portfolio link>
This experience - and the fact that there are so few results more than six months later - suggests that there is still a need for a) more RTL-supporting D8 themes and b) documentation to make it clear when a theme does support RTL languages.
As a development shop that has quite a lot of multlingual work, I think it would be great if Netuxo had the resources to create and maintain a simple RTL supporting theme ourselves and make it available to the community. Sadly we don't have that capacity at the moment - so, for now, something else for the (long!) list...