"Outline > simple line" does not grant access to the options/library of lines symbols

[gioman]

What is the bug or the crash?

Fora polygon layer when you choose its style as "outline > simple line" QGIS does not grant access to the options/library for line synmbols, but if you choose "outline > marker line" then it correctly shows the options/library for point symbols

VS

Steps to reproduce the issue

Add a polygon layer

Style it with "outline > simple line"

Versions

3.34
3.38
master

Libraries
QGIS version	3.39.0-Master
QGIS code revision	29bf082ed3
Qt version	5.15.13
Python version	3.12.5
GDAL/OGR version	3.10.0dev-6339b46c60
PROJ version	9.4.0
EPSG Registry database version	v11.004 (2024-02-24)
GEOS version	3.12.2-CAPI-1.18.2
SQLite version	3.45.1
PDAL version	2.6.3
PostgreSQL client version	16.2
SpatiaLite version	5.1.0
QWT version	6.2.0
QScintilla2 version	2.14.1
OS version	Windows 11 Version 2009
This copy of QGIS writes debugging output.
Active Python plugins
fccn_validator	1.0.0
lizmap	4.3.19
openlittermap	1.0.0
db_manager	0.1.20
processing	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

[nyalldawson]

This isn't a bug -- the symbol library pane is only shown when you are configuring a sub-symbol for a symbol layer, so it's only visible for symbol layer types which use sub symbols. Marker line uses these, simple line does not.

[gioman]

This isn't a bug -- the symbol library pane is only shown when you are configuring a sub-symbol for a symbol layer, so it's only visible for symbol layer types which use sub symbols. Marker line uses these, simple line does not.

@nyalldawson ummm... I see... but then what about if I want to style the outline of a polygon with a line style I previously saved in my library? Isn't possible? Seems weird (from a user point of view) considered all we can do with symbology in QGIS.

[nyalldawson]

@gioman yeah, that's a good point. I think if we want to handle this then we could expose line symbols in the top-level browser for polygon layers too.

[github-actions]

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