we want to upgrade our environment Horizon 7.5 to the latest version 7.13. The reason is the expiring Flash Player support from January 2021. Do you have experiences with it? What do I have to consider?
No issue should arrise, it's in the upgrade path : https://www.vmware.com/resources/compatibility/sim/interop_matrix.php#upgrade&solution=260
Now I'd recommend to check vSphere version and Operating System as well to be sure it's in the supported list.
Upgrading to 7.13 will also let you use Instant clone VM even with a Standard license as Composer is now depreciated and will be removed in next version of Horizon 8. (7.13 is the latest Horizon7 release so no 7.14 version is coming ).
FYI many functionalities from Horizon 8 has been backported to Horizon 7.13 like CRBC 2.0 to allow up to 32GB RAM (only with vSphere 7).