problem with fixed width, you have the same problem in your demo at ​https://jqueryui.com/sortable/#display-grid if you try taking the 1 and moving it to where the 4 is you will notice you must drag it over the lower half of the 4 before it moves.

If you go to the theme roller page here ​theme roller you will see that the radio buttons and checkbox buttons have a solid red background when unchecked, and when the radio button is selected it becomes a smaller red dot, and for the checkbox it is even worse where there is no visible checkmark, and only the corresponding text changes color. So, with the Blitzer theme it is difficult to visually tell if a checkbox or radio button is selected. I would expect that in their unchecked state, that the radio button and the checkbox button would have a white background or something similar so that the checked state would be more apparent.

In jquery ui 1.12.1 it seems that when reinitializing resizable or changing the "handles" setting removes the previous handles because it assumes that they will be re-added

however if you use the object notation where you define existing DOM elements for the handles, these dom elements are removed and handles disappear

here is a jsfiddle replicating the scenario : ​https://jsfiddle.net/annam/2cg12b1j/

change the jquery ui include to 1.11.4 to see how it worked before

thanks! Anna