WowAce

below errors consistently happen since last patch.

Message: [string "PetsAndMountsMenuModelFrame:OnLoad"]:1: attempt to call method 'SetBackdropBorderColor' (a nil value)
Time: Tue Aug 3 04:55:44 2021
Count: 1
Stack: [string "PetsAndMountsMenuModelFrame:OnLoad"]:1: attempt to call method 'SetBackdropBorderColor' (a nil value)
[string "@Interface\AddOns\PetsAndMountsLoader\Loader.lua"]:21: in function <Interface\AddOns\PetsAndMountsLoader\Loader.lua:17>

Locals: self = <unnamed> {
0 = <userdata>
errorMessage = "An error occurred while loading the add-on Blizzard_Collections which is required for Pets & Mounts to load. Manually opening your collections panel can fix that. For reporting purpose, this is the error returned by the UI: %s"
}
event = "PLAYER_ENTERING_WORLD"
A = <unnamed> {
0 = <userdata>
errorMessage = "An error occurred while loading the add-on Blizzard_Collections which is required for Pets & Mounts to load. Manually opening your collections panel can fix that. For reporting purpose, this is the error returned by the UI: %s"

additional error message 

Message: Interface\AddOns\PetsAndMounts\Variables.lua:455: attempt to call global 'GetBarberShopStyleInfo' (a nil value)
Time: Tue Aug 3 05:02:50 2021
Count: 2
Stack: Interface\AddOns\PetsAndMounts\Variables.lua:455: attempt to call global 'GetBarberShopStyleInfo' (a nil value)

Locals: