SHORT DESCRIPTION: If we don't do compatibility checking (e.g. Thunderbird add-ons), add a link to the versions page that looks like this: http://cl.ly/063V3J3F2B252b281V18 LONGER RAMBLINGS: Currently, applications like Thunderbird are hosted on AMO. We don't do any sort of compatibility checking anyway; we just show a download button. If the user is using a version of the application that isn't supported by the current add-on version (but is by another add-on version), they will download the add-on then think it doesn't work at all. For example, let's say current version of Lightning doesn't work with Thunderbird 9, but the previous one did. Someone using Thunderbird 9 may assume that no versions work. So, for add-ons that we don't do any compatibility checking on, we should add a message below indication what versions of the app the current version is available for. And, we should link to the versions page. (Note: This is basically just bug 685685, however I felt it was easier for developers to not have to read that entire thread.)
Are Firefox extensions the only thing we do compatibility checking on? So anything NOT firefox extensions would get this extra string + link?
Whoops, I should clarify. It should only do it for extensions (not themes, search, etc) where appsuported (in buttons.js) is false. So, for example, Thunderbird extensions, where we show "Continue to Download": http://cl.ly/3i2M2N3I1M1I1L2t0A1B I'm not sure the exact conditions; buttons.js is fairly confusing. Feel free to use your judgement -- if it seems like someone would benefit from a link to the versions page, add it.
Verified as fixed in https://addons-dev.allizom.org/en-US/ on FF11 Attaching postfix screenshot for this issue. Closing bug.