Disabling Render Plugins
Disabling the Cycles add-on while it is active in the viewport can cause Foam to hard crash Blender. If you need to do this it's best to restart Blender after disabling the Cycles add-on. For 4.0 and later disabling Hydra while it is in use can also cause problems.
wm.context_toggle and wm.context_toggle_enum (Blender 4.0.0 - 4.0.2)
Clicking in the Context Attributes (internal name data_path) entry in the widget configuration dialog while either of these (and possibly other) operators is selected results in an immediate hard crash of Blender.
For now Foam will not allow you to configure either of these operators directly. Instead you will need to add the parameters in JSON in the manual operator editor. To toggle the N-panel you would need to enter:
{"data_path": "space_data.show_region_ui"}
This has been logged with Blender as Issue #116854 A fix is present in Blender 4.1.0 Alpha as of January 11 2024.
Right-Click Context Menu (Blender 3.6.0-4.0.2)
On string fields that allow searching, including the Operator, Tool and Setting search boxes, right clicking can hard crash Blender 3.6.0 to 4.0.1. This is because of an internal Blender issue. Logged with Blender as issue #115437
A fix for this is present in Blender 4.1.0 Alpha.
Quad View
Blender 3D Views can be divided into four regions with three of them locked to orthographic views. Popup foams work in each of these as if they were separate areas. However Persistent foams are disabled for now until quad view is closed. Persistent foams will work in separate 3D Views however.
Upgrading
Because we store the enabled/disabled state of foams in Blender preferences, disabling and re-enabling Foam in order to upgrade it can reset all of your foams to be enabled. This can cause unexpected behaviour if several foams have the same activation key.
Upgrading past Foam 1.0.0 should no longer reset preferences as they are stored outside of Blender.