Views 5.x-1.6-beta4

I upgraded my version of Views this morning from Views 5.x-1.5 to Views 5.x-1.6-beta4 and am noticing an odd behavior. I wanted to run it by someone in case I am making a mistake before I submit it as a bug.

I have created a view with the filter 'Taxonomy: Terms for Forums' and for some reason it will only let me select one term- with the terms showing up in a single line box. However, if I select 'Taxonomy: Terms for anything else' then it works fine- with a multiple-line display of all the the terms and the ability to select multiple terms.

Is there some kind of setting that I could have messed with on my Forums taxonomy to cause it to not work??