Regression: deleting imagery layer changes active layer

[Famlam]

What steps will reproduce the problem?

1. Load any map data
2. Add one imagery layer ("A")
3. Add another imagery layer ("B")

--> The sequence of layers should now be [1] "A", [2] "B", [3] data layer, with the data layer being the active layer

4. Delete layer "B" (at position 2 in the list with layers)
5. The active layer changes from the data layer to layer "A"

This is a regression: it did not occur in r18822, does occur in r18875 and r18893
The most suspicious commit (without having proof, just based on description) is r18837, hence cc taylor.smock

What is the expected result?

Behavior of current stable: deleting an layer that is not the active layer does not change the active layer

What happens instead?

The active layer changes

Please provide any additional information below. Attach a screenshot if possible.

Note: reproduction is also possible if you change step 4 to remove layer "A"
Reproduction is _not_ possible if the active layer isn't on top of the list (e.g. highest index)

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2023-11-02 13:14:51 +0100 (Thu, 02 Nov 2023)
Revision:18893
Build-Date:2023-11-06 02:30:59
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (18893 nl) Windows 10 64-Bit
OS Build number: Windows 10 Home 2009 (19045)
Memory Usage: 442 MB / 2012 MB (155 MB allocated, but free)
Java version: 17.0.8+7-LTS, Azul Systems, Inc., OpenJDK 64-Bit Server VM
Look and Feel: com.sun.java.swing.plaf.windows.WindowsLookAndFeel
Screen: \Display0 1920×1080 (scaling 1.10×1.10)
Maximum Screen Size: 1920×1080
Best cursor sizes: 16×16→32×32, 32×32→32×32
System property file.encoding: Cp1252
System property sun.jnu.encoding: Cp1252
Locale info: nl_NL
Numbers with default locale: 1234567890 -> 1234567890
VM arguments: [-Djpackage.app-version=1.5.18822, --add-modules=java.scripting,java.sql,javafx.controls,javafx.media,javafx.swing,javafx.web, --add-exports=java.base/sun.security.action=ALL-UNNAMED, --add-exports=java.desktop/com.sun.imageio.plugins.jpeg=ALL-UNNAMED, --add-exports=java.desktop/com.sun.imageio.spi=ALL-UNNAMED, --add-opens=java.base/java.lang=ALL-UNNAMED, --add-opens=java.base/java.nio=ALL-UNNAMED, --add-opens=java.base/jdk.internal.loader=ALL-UNNAMED, --add-opens=java.base/jdk.internal.ref=ALL-UNNAMED, --add-opens=java.desktop/javax.imageio.spi=ALL-UNNAMED, --add-opens=java.desktop/javax.swing.text.html=ALL-UNNAMED, --add-opens=java.prefs/java.util.prefs=ALL-UNNAMED, -Djpackage.app-path=%UserProfile%\AppData\Local\JOSM\JOSM.exe]
Dataset consistency test: No problems found

Plugins:
+ OpeningHoursEditor (36126)
+ imagery_offset_db (36126)
+ pbf (36176)
+ pt_assistant (631)
+ reverter (36126)
+ tageditor (36126)
+ turnlanes-tagging (0.0.5)
+ undelete (36126)
+ utilsplugin2 (36178)

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/Potlatch2&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Lane_and_Road_Attributes&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/PublicTransport&zip=1
+ %UserProfile%\Documents\tijdelijke bestanden\josm-eigen.mappaint.mapcss
+ https://josm.openstreetmap.de/josmfile?page=Styles/Sidewalks&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/ParkingLanes&zip=1

Validator rules:
+ %UserProfile%\Documents\tijdelijke bestanden\josm-eigen.validator.mapcss
+ https://josm.openstreetmap.de/josmfile?page=Rules/SuspiciousSwimming_Pool&zip=1
+ https://raw.githubusercontent.com/osm-fr/osmose-backend/master/plugins/TagFix_Destination.validator.mapcss
+ https://raw.githubusercontent.com/osm-fr/osmose-backend/master/plugins/Colour.validator.mapcss
+ https://raw.githubusercontent.com/osm-fr/osmose-backend/master/plugins/notprefix.validator.mapcss
+ https://raw.githubusercontent.com/osm-fr/osmose-backend/master/plugins/TagFix_MultipleTag2.validator.mapcss
+ https://raw.githubusercontent.com/Famlam/OsmMapcssValidationNL/main/netherlands.validator.mapcss

Last errors/warnings:
- 00000.949 W: extended font config - overriding 'filename.Myanmar_Text=mmrtext.ttf' with 'MMRTEXT.TTF'
- 00000.952 W: extended font config - overriding 'filename.Mongolian_Baiti=monbaiti.ttf' with 'MONBAITI.TTF'
- 00001.909 E: java.security.KeyStoreException: Windows-ROOT not found. Oorzaak: java.security.NoSuchAlgorithmException: Windows-ROOT KeyStore not available

[taylor.smock]

Closed as duplicate of #23057.
gaben has a patch over on #23057 which I'm currently reviewing. He does include a non-regression test so that this doesn't happen again.

[Famlam]

I can confirm this issue is fixed with the patch (r18895) applied, thank you!

[taylor.smock]

No problem. Thank you for using josm-latest so that josm-tested is less likely to have changes in behavior that I think is OK, but isn't.