When in the language menu, you can see "Inglise (US)" (a little below "English (US)"). Kind of sounds like "English"? That's because it is english in estonian. This is a very long-standing bug, but should be fixed. It's supposed to be "Eesti (ET)".
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This ticket is a language translation request and is not supported on this bug tracker.
Please use the Crowdin Minecraft Translation Project for all translation change or add requests.
But this was fixed at crowdin some time ago and will be fixed in the game when the translations are pulled from crowdin. Expect that short before release of 1.9