Mac: Drawing artifacts of caret when changing font

When font is changed some drawing artifacts of caret is seen also when font Hinrangana is used text does not drawn at same horizontal line. Attached is the example to reproduce it.
Steps:
See attached png file.

1) Run same example
2) Click line edit
3) Change Input Method to Hiragana
4) Type k
5) Type a (KA will be changed to "か")
6) Type k

Expected: The horizontal text drawn position does not change.
Actual: Unexpectedly, the text drawing position is goes up slightly.

To see the artifact just follow these steps of changing fonts without Hirangana:
1) Run attached example
2) Click line edit
3) Type "a"
4) Change font to the "Al Nile"
5) Change font to the "Al Bayan"
6) Click line edit again