Perform a gravity jump followed by a springball jump to reach the left side door. The gravity jump will only get high enough if it is within the last two frames, and the Spring Ball jump must be delayed and near the peak of the jump.

Requires:

{
  "notable": "Reverse Acid Dive"
}
{
  "obstaclesNotCleared": [
    "A"
  ]
}
"HiJump"
"canTrickyJump"
"canGravityJump"
{
  "or": [
    "h_crouchJumpDownGrab",
    {
      "and": [
        "canTrickyCarryFlashSuit",
        "canDownGrab"
      ]
    }
  ]
}
"canSpringBallJumpMidAir"
{
  "heatFrames": 50
}
{
  "acidFrames": 50
}
{
  "gravitylessHeatFrames": 300
}
{
  "gravitylessAcidFrames": 300
}

Unlocks doors:

{"types":["super"],"requires":[]}
{"types":["missiles","powerbomb"],"requires":["never"]}

Dev note: It is possible to do this with a flash suit, and no crouch jump, but it requires a frame perfect jump and then a Spring Ball jump within 3 pixels of its peak.