Multiple style issues.

Is there an existing issue for this?

• I checked and did not find my issue in the already reported ones

Describe the bug

Creation and applying of styles misbehave in many scenarios.

1. Original modules are overwritten instead of added when using append mode when those modules are not used in the edit that the style is applied to.
2. Module order setting is ignored if the above scenario happens.
3. If there are already two (or more) of the same modules active, the module order of the originals is changed.
4. Every so often during creation of a style many completely unrelated modules are added to that style.

Steps to reproduce

See all the attached videos.

Expected behavior

That styles do what they are supposed to do.

Logfile | Screenshot | Screencast

• Just in case, creation of a style:

https://github.com/user-attachments/assets/6a95515a-071d-4066-9568-b56e04a3178d

1. .2) Overwriting originals/wrong order:

Wrong behaviour:

https://github.com/user-attachments/assets/0f0436e1-a50c-4dfb-8798-85da4ef687f5

"Correct" when modules are already active:

https://github.com/user-attachments/assets/c3b19602-0fe3-438b-babc-16f6b6a66205

3. Module order of the originals is changed:

https://github.com/user-attachments/assets/923da598-be3f-4378-b06b-2383f64bf509

4. Unwanted extras:

https://github.com/user-attachments/assets/f13badef-e73f-47a6-8a2c-a1ba9c1bdf5c

Commit

n/a

Where did you obtain darktable from?

self compiled

darktable version

4.8.1 / 5.0.1 / 5.2.1 / 5.4.1

What OS are you using?

Linux

What is the version of your OS?

debian (seen this with the last 3 stable version: 11, 12, 13)

Describe your system

I've seen this on many version and systems. Currently self build on linux, but I've also used a, at the time current flatpak version (mainly 5.0.X).

Are you using OpenCL GPU in darktable?

Yes

If yes, what is the GPU card and driver?

NVIDIA GeForce RTX 2060 SUPER (not relevant, see this also without opencl)

Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip

I've been having most of the above mentioned style issues for years and mentioned this multiple times on IRC. I haven't created a bug report before because the only other person that seems to have/had issues at times is @wpferguson. We did do some investigating at the time but nothing really seem to have come from that.

I decided to try once again with the newest darktable version and do something that seems to be simple:

Create two starting points for dealing with printing; One for sharpening (D&S) and one for the shadows (tone curve). Make sure these two modules are high up in the pipeline to not mess with the already existing edit.

All that I've posted here is the result of trying to do just that and failing to make it work reliably.

PS: The adding of unrelated modules when creating a style is new (first seen by me with version 5.2.1).

EDIT Not shown above but I also run into situations that if I apply a style (the above mentioned for example) to an older edit that already has two of the same modules present (no name and 1) that one of those is overwritten and the order is switched (no name overwritten and 1 placed high in the pipe. The style version replaces the no name version and its position).

Start by reproducing the style creation and application scenarios shown in the attached videos, including append mode, duplicate modules, module ordering, and unrelated modules. Compare behavior across the reported darktable versions; done means styles preserve existing modules and order and do not add unrelated modules.