Tasks are in different order after dragging them manually and then reloading the page

For demonstrating this issue, I created a set of non-urgent, important tasks numbered 1-5 and a set of normal tasks, which are in a sequence of a-e.

I) The list now looks 5-4-3-2-1-e-d-c-b-a, as it is intended.

II) If I now reorder the tasks by dragging, in my example e-5-d-4-c-3-b-2-a-1, this is working fine, first.

III) But if the page is reloaded (by pressing F5, CMD-R, logging out and in again and so on), the order is somehow randomly destroyed, in my example it is 4-3-2-1-e-5-d-c-b-a now.

IV:) If I now again try to reorder the tasks as I like (5-4-3-2-1-e-d-c-b-a) and reload the page, the new order is 3-2-1-e-5-d-4-c-b-a, thus it seems that Week Plan only "remembers" the first task that has been dragged... strange, isn't it?

I):


II):

III):


IV:)



As this might be related to the bug above: Also, I sometimes cannot drag a task from another week day or from the goals list to the end of a week days task list. It just "flies" back to where I dragged it from. Additionally, I am not able to create a task in the "pending" list. I have to create a task on a different day and drag it to the pending list, then. All of these bugs and glitches might relate to each other. Feel free to re-edit my ticket if this is not the case.

Browsers: Firefox 38 on Xubuntu / Ubuntu 14.04 and Chrome 43.0.2357.51 on an iPad w/ iOS 8.3

Cheers
Dennis