Deleting "all other values" breaks categorise symbology

[pablolivares]

What is the bug or the crash?

A video to explain

It's like this issue #43651 but it's not related to datetime attribute

Steps to reproduce the issue

Create layer with 2 fields
Create few features 
Create a categorised symbology using expressions: "field1" + "field2"
Uncheck "all other values" in symbologie

Versions

<style type="text/css"> p, li { white-space: pre-wrap; } </style>

Version de QGIS	3.34.10-Prizren	Révision du code	113de9e
Version de Qt	5.15.13
Version de Python	3.12.5
Version de GDAL/OGR	3.9.2
Version de Proj	9.4.0
Version de la base de données du registre EPSG	v11.004 (2024-02-24)
Version de GEOS	3.12.2-CAPI-1.18.2
Version de SQLite	3.45.1
Version de PDAL	2.6.3
Version du client PostgreSQL	16.2
Version de SpatiaLite	5.1.0
Version de QWT	6.2.0
Version de QScintilla2	2.14.1
Version de l'OS	Windows 10 Version 2009
Extensions Python actives
clipper	1.2
DigitizingTools	1.5.2
LienBDDico	version 1.0
LinearReferencing	1.0.2
linking_relation_editor	v1.4.0
LocatePoints	0.3.4
lrs	1.2.3
lrseditor	1.3.1
qchainage	3.0.1
QlrBrowser	3.0.0
segment_reshape_plugin	0.1.6
db_manager	0.1.20
MetaSearch	0.3.6
processing	2.12.99

Version de QGIS 3.34.10-Prizren Révision du code [113de9e](https://github.com/qgis/QGIS/commit/113de9e1) Version de Qt 5.15.13 Version de Python 3.12.5 Version de GDAL/OGR 3.9.2 Version de Proj 9.4.0 Version de la base de données du registre EPSG v11.004 (2024-02-24) Version de GEOS 3.12.2-CAPI-1.18.2 Version de SQLite 3.45.1 Version de PDAL 2.6.3 Version du client PostgreSQL 16.2 Version de SpatiaLite 5.1.0 Version de QWT 6.2.0 Version de QScintilla2 2.14.1 Version de l'OS Windows 10 Version 2009

Extensions Python actives
clipper
1.2
DigitizingTools
1.5.2
LienBDDico
version 1.0
LinearReferencing
1.0.2
linking_relation_editor
v1.4.0
LocatePoints
0.3.4
lrs
1.2.3
lrseditor
1.3.1
qchainage
3.0.1
QlrBrowser
3.0.0
segment_reshape_plugin
0.1.6
db_manager
0.1.20
MetaSearch
0.3.6
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

[agiudiceandrea]

@pablolivares, thanks for reporting. I cannot replicate the issue using QGIS 3.34.10 on Windows 10 following the provided steps. Please try if the issue occurs also using a new QGIS user profile. If it does, please provide a sample layer and project and / or more detailed steps to replicate the issue.

[pablolivares]

@agiudiceandrea I've tried using a different user profile, but I'm still having trouble.

I attach a sample data
test.zip

Thanks for your support

[agiudiceandrea]

I can confirm the issue occurs if the layer is a GeoPackage layer, while it doesn't occur e.g. if the layer is an ESRI Shapefile or a Memory layer.

[agiudiceandrea]

The issue occurs only using the + operator. As a workaround, you can use the || operator or the concat function in order to join the text fields' values in the expression.