Beginning with 3.6.1 nav menu breaks when clicking update in nav menus

[petercng]

Beginning with 3.6.1 nav menu breaks when only clicking update in nav menus. Menus Settings looses its checked location after selecting UPDATE. You can select a location, but it will not save it. UPDATE action corrupts something in the database, as a SQL import of the uncorrupted database will correct the scrambled menu. Went UN-noticed until I attempted to add page to nav menu in 3.7.1. I have 97 pages and use the responsive theme. I have duplicated this on two different hosts. It works correctly on 3.6.

[nacin]

Does it work in 3.7.1?

[petercng]

Replying to nacin:

Does it work in 3.7.1?

No.
It has the same problem. I was using 3.7.1 when I first observed the problem. I attempted to add a new page. I went back to 3.5.1 and tested each version until I observed the problem beginning with 3.6.1. Although in 3.6 you need to save your menu twice for it to remember the location setting of the menu.

[SergeyBiryukov]

The only related change in 3.6.1 was #25064. Might as well be a manifestation of #14134.

[chriscct7]

No reporter feedback in 2 years. Likely #14134