Starting with the release of Strategy ONE (March 2024), dossiers are also known as dashboards.
When you use color by attribute and do not change the color of a customized color, the element number of your visualization may change after performing actions like Filter, Keep Only, and Exclude. If you export the dossier to PDF or save the dosser then reopen it, the color will appear different.
When you use the default color, the color is set according to the color mapping rule: Color mapping between widgets is maintained as a global property across the whole dashboard level. The rule for mapping color is "first come, first served." With this color mapping rule, the element's color is not saved when you use the default color. This is so that only run-time color mapping is cached. Thus, every time you reopen a dossier, all previously cached mapping is lost.
If you want the keep the color constant, please set the color manually.