+Version 1.6.40 [June 21, 2023]
+ Fixed the eXIf chunk multiplicity checks.
+ Fixed a memory leak in pCAL processing.
+ Corrected the validity report about tRNS inside png_get_valid().
+ Fixed various build issues on *BSD, Mac and Windows.
+ Updated the configurations and the scripts for continuous integration.
+ Cleaned up the code, the build scripts, and the documentation.
+