Only a small number of changes in the LR 12.3 SDK compared to the LR 12.0 SDK:
Lightroom Classic SDK Programmers Guide -- no changes according to Adobe Acrobat.
API Reference
LrDevelopController
These parameter names were added: local_Amount, local_Maincurve, local_Redcurve, local_Greencurve, local_Bluecurve
Undocumented Changes
My automated scripts found the following changes:
photo:getFormattedMetadata ("fileType") and photo:getRawMetadata ("fileFormat") can return the new types "JXL" (for JPEGXL) and "AVIF".
photo:getFormattedMetadata ("trimmedDuration") returns the trimmed duration of a video, as it appears in the Metadata panel.
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