Hello:

?ש = \u05e9 = "HEBREW LETTER SHIN"
?ָ = \u05b8 = "HEBREW POINT QAMATS"

i.e., "\u05e9\u05b8", should display with the qamats right under the shin,
which is the case under emacs 25 and earlier, but fails in emacs 26: The
qamats is printed below but to the side, and not right under the letter
shin. This happens regardless of the font used, and with professional
OTF fonts that are designed to handle combining characters correctly,
and which are handled correctly by emacs 25 and earlier. This problem is
not unique to Hebrew, but is true for any RTL language I've checked
inclinding Arabic and Farsi.


In GNU Emacs 26.1 (build 3, x86_64-pc-linux-gnu, GTK+ Version 2.24.32)
 of 2019-03-08 built on curry
Windowing system distributor 'The X.Org Foundation', version 11.0.11906000
System Description:    Ubuntu 18.04.2 LTS

Recent messages:
For information about GNU Emacs and the GNU system, type <f1> C-a.
Mark set
Mark saved where search started
Saving file /home/gmayer/brain/main.brain...
Wrote /home/gmayer/brain/main.brain
Making completion list...
Quit [13 times]
Mark set [2 times]
delete-backward-char: Beginning of buffer [2 times]
You can run the command ‘unicode-info’ with M-x un-i RET

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