On a fresh install, both local (valet) and on production server, the tags in the input fields that contain the different language option won't show.
On the current stable build (351) nothing shows at all, with edge updates enabled (357) and the translate plugins updated to 1.2.2 the CMS section does show the translation options for the URL of cms pages (which is an edge feature of the translate plugin at the time of writing).
Translation of custom plugins by implementing the Translate behaviour in a model also does not trigger language options. Tested on inputs and rich editors.
Build 351:

Build 357:

UPDATE
When saving a CMS page a internal server error occurs:

Unable to replicate this, take a screenshot of your languages settings page. Is it possible you are missing a default language?

Ok, sorry I'm a bit lost here. Will need end-to-end replication instructions, from a fresh October installation. As per the contribution guidelines, please provide the exact steps you are taking for the issue to occur. This will be used for peer review.
Will make a screencap soon with step by step instructions.
On Saturday, 3 September 2016, Samuel Georges [email protected]
wrote:
Ok, sorry I'm a bit lost here. Will need end-to-end replication
instructions, from a fresh October installation. As per the contribution
guidelines, please provide the exact steps you are taking for the issue to
occur. This will be used for peer review.—
You are receiving this because you authored the thread.
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Hmm, never came around to provide further replication of the issue. I've haven't experienced any problems regarding this but the question remains: is translatable suppose to provide title and meta tags translation support?
Not as part of the UI. You can translate them easily by using the |_ twig filter, eg: {{ this.page.meta_title|_ }}.
I think this isn't relevant anymore. Hasn't happened anymore and it seems nobody else experiences this problem.