Overbar using ~{} cannot be entered in label

Description

~ should create the overbar for active low. This was recently broken in current nightly build (info below) and the ~ is rendered as a ~ rather than the overbar. Additionally, I see in a schematic (I copy pasted from an earlier 5.99 nightly build created schematic) the ~FOO overbar label morphed into ~{FOO}

Overbar not rendered for ~ in label. Also, the label still rendered with overbar (FOO) can't be edited, and ~{FOO} is actually rejected. I haven't figured out a way to repro the ~{FOO} issue (which morphed from ~FOO) reliably yet.

Steps to reproduce

1. Create label
2. Enter label name as ~FOO
3. Observe rendered label in schematic has no overbar but is rendered as ~FOO instead

KiCad Version

Application: KiCad Schematic Editor

Version: 5.99.0-unknown-8b2b3ca797~130~ubuntu21.04.1, release build

Libraries:
	wxWidgets 3.0.5
	libcurl/7.74.0 OpenSSL/1.1.1j zlib/1.2.11 brotli/1.0.9 libidn2/2.3.0 libpsl/0.21.0 (+libidn2/2.3.0) libssh/0.9.5/openssl/zlib nghttp2/1.43.0 librtmp/2.3

Platform: Linux 5.11.0-22-generic x86_64, 64 bit, Little endian, wxGTK, ubuntu, x11

Build Info:
	Date: Jul  4 2021 18:59:29
	wxWidgets: 3.0.5 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
	Boost: 1.74.0
	OCC: 7.5.1
	Curl: 7.74.0
	ngspice: 34
	Compiler: GCC 10.3.0 with C++ ABI 1014

Build settings:
	KICAD_USE_OCC=ON
	KICAD_SPICE=ON