First color for lineburst symbol is not stored in color button widget

[mblesius]

What is the bug or the crash?

For lineburst symbols, the first color button in the symbol layer properties does not keep the selected color. The color is lost, when you leave the symbol layer properties. However, the lineburst is still rendered as before.

Steps to reproduce the issue

Lineburst_color_button.mp4

Versions

QGIS version	3.28.3-Firenze	QGIS code revision	c12bcb2
Qt version	5.15.3
Python version	3.9.5
GDAL/OGR version	3.6.2
PROJ version	9.1.1
EPSG Registry database version	v10.076 (2022-08-31)
GEOS version	3.11.1-CAPI-1.17.1
SQLite version	3.39.4
PDAL version	2.4.3
PostgreSQL client version	unknown
SpatiaLite version	5.0.1
QWT version	6.1.6
QScintilla2 version	2.13.1
OS version	Windows 10 Version 2009
Active Python plugins
db_manager	0.1.20
grassprovider	2.12.99
MetaSearch	0.3.6
processing	2.12.99
sagaprovider	2.12.99

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

No response