Sprites can still appear in front of the border

[gardners]

Reported by a user:

Second topic: C64 sprites (just basic sprites, but more difficult to
demonstrate)

Please enter the following code in C64 mode:

POKE53280,6:POKE53281,0
POKE53248,23:POKE53249,55:POKE2040,64:POKE53287,1:POKE53269,1
FOR T=4096 TO 4159:POKE T,0:NEXT
POKE4096,128:POKE4098,1:POKE4099,128:POKE4101,1
POKE4102,192:POKE4104,3:POKE4105,192:POKE4107,3
POKE4108,224:POKE4110,7:POKE4111,224:POKE4113,7

Here you can see that the sprites is being displayed not only on
screen but also in front of the border. Maybe this can be seen more
clearly if the screen color is white and the border color is black:

POKE53280,0:POKE53281,1

Now the left transition from black border to white screen is not as
straight as it should be. One can see the sprite clearly reaching into
the border.