Pages not saved under Contexts

I'm using MODX Revolution 2.1.4-pl (traditional) on Ubuntu with PHP 5.3

I'm new to Modx, but I'm a seasoned PHP developer, and I just can't figure this issue out.

I want to create a site that has 3 contexts which match to 3 subdomains.

I create my 3 contexts: web, mobile, facebook, and can see these in the Resource Tree.

I then create a home page under each context: web home, mobile home, facebook home.

All fine.

However, when I edit any of these pages, and save, the other 2 pages appear under the context of the page I am editing.

eg

if I edit mobile home, and save, I now see web home, mobile home and facebook home all under the mobile context

This is happening at code level.

If I look at my mysql log when I save, I can see that the code is updating the context for all my pages, and not just the page I am editing.


4749 Query UPDATE `modx_site_content` SET `context_key` = 'mobile' WHERE `id` = 9
4749 Query UPDATE `modx_site_content` SET `context_key` = 'mobile' WHERE `id` = 7
4749 Query UPDATE `modx_site_content` SET `context_key` = 'mobile' WHERE `id` = 8

Is this a bug in the version I am using, or am I doing something wrong?

https://forums.modx.com/thread/71655/

Do I win a prize?

Confirmed that 2.1.5 fixes the bug