"Watch topic" feature keeps unwatching

[Noxious89123]

I've got the bike picture challenge thread set as a watched topic so that I get notifications when it's updated, but after every couple of times I've looked at the topic, it removes itself from my watched list.

Why does it keep doing this?

Using Firefox 16.0.1, but was doing it on 15 as well.
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'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[Noxious89123]

Le bump?
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'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[Easter Bunny]

I'm getting the same
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The light at the end of the tunnel is an oncoming train!

[Noxious89123]

It's a massive pain in the arse!
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi