This fix addresses the issue when the player character first appears in the level, the character mesh appears discolored and too bright in Unreal 5.1 compared to how it did in Unreal 4.26. This effect only appears around the spawn point and it's more obvious towards the character's feet. It was caused by the decal M_Mod_Water_DCL_Tunnel_Inst that was placed below the character's spawn point.
This fix sets the panel widget ScaleBox_Interactions from Stretch: "Scale to Fit" to "Fill" because Widget_HUD was not displaying any of the possible player interactions when BP_Character overlaps with BP_Interact. These interactions should be displayed on Widget_HUD by adding Widget_InteractionsLine as a child. The blueprint was working as intended, but the panel widget setting wasn’t allowing Widget_InteractionsLine to be visible to the player. This bug appeared after upgrading from Unreal 4.26 to Unreal 5.1.
