This character is a Nonspacing Mark and inherits its script property from the preceding character.
The glyph is not a composition. Its width in East Asian texts is determined by its context. It can be displayed wide or narrow. In bidirectional text it acts as Nonspacing Mark. When changing direction it is not mirrored. U+031B prohibits a line break before it. The glyph can be confused with one other glyph.
The Wikipedia has the following information about this codepoint:
The horn (Vietnamese: dấu móc or dấu râu) is a diacritic mark attached to the top right corner of the letters o and u in the Vietnamese alphabet to give ơ and ư, unrounded variants of the vowel represented by the basic letter. In Vietnamese, they are rarely considered as diacritics; but rather, the characters ơ and ư are considered as different letters from o and u.
Representations
System
Representation (click value to copy)
Nº
795
UTF-8
CC 9B
UTF-16
03 1B
UTF-32
00 00 03 1B
URL-Quoted
%CC%9B
HTML hex reference
̛
Wrong windows-1252 Mojibake
◌̛
Encoding: GB18030 (hex bytes)
81 30 BF 33
AGL: Latin-4
uni031B
AGL: Latin-5
uni031B
Adobe Glyph List
horncmb
RFC 5137
\u'031B'
Bash and Zsh inside echo -e
\u031B
C and C++
\u031B
C#
\u031B
CSS
\00031B
Excel
=UNICHAR(795)
Go
\u031B
JavaScript
\u031B
Modern JavaScript since ES6
\u{31b}
JSON
\u031B
Java
\u031B
Lua
\u{31B}
Matlab
char(795)
Perl
"\x{31B}"
PHP
\u{31b}
PostgreSQL
U&'\031B'
PowerShell
`u{31B}
Python
\u031B
Ruby
\u{31b}
Rust
\u{31b}
Click the star button next to each label to set this representation as favorite or remove it from the favorites. Favorites will be shown initially. (Favorites are stored locally on your computer and never sent over the internet.)