Vertical misalignment of arrays

Created by: kwkbtr

Minimal test case: https://jsbin.com/vedulobegu/1/edit?html,output

The top padding of (the first line of) a LaTeX array changes depending on existence of horizontal rules inside the array. In the above test case, top edges of two arrays are misaligned with each other. It seems that the difference comes from this code: https://github.com/mathjax/MathJax/commit/577b37ee60cd86b782366cda069594c3bb76ef41#diff-2f75a19c51cea069923d362e44d2deb0R154 Is this expected behavior? Is there any workaround to align them?