no, bring back that defense

Dependencies

• [2] EHSUSZMK more idiomatic variable names
• [*] BLWAYPKV extract a module
• [*] RT6EV6OP delegate update events to drawings

Change contents

• edit in drawing.lua at line 244
  [5.254]

  [2.17]
  + if drawing.y == nil then

  + -- something invalidated all the y's; just wait for a draw

  + return

  + end