“New message” / “Rename variable/list” popup hides instantly (touchscreen)

• Press the “new message”/“rename …” button longer
  or
  
• Move the block into a position where if you press the button, the popup will appear under your finger

Can't drag code into other sprites (touchscreen)

• Tap and hold the target sprite. With another finger, grab the blocks, and release them over the sprite list, but avoid touching the other sprites in the list. (also avoid touching backpack items)
  or
  
• Release the blocks while they are still moving, so that your finger is over the sprite but the blocks aren't yet (was inconsistent and it worked only because of the inaccuracies of trying to do it)

Can't backpack blocks (touchscreen)

• Move the blocks over the sprite list and hold them. With another finger, tap and hold a point inside the backpack where it isn't covered by backpacked items, and release the blocks over the sprite list.

Blocks aren't sensing key presses (after clicking focusable buttons; some of them don't get outlined when pressing keys)

• Click on the stage or the space around it

Scratch is dragging the wrong sprite

• Grab a part of the sprite that doesn't overlap with other sprites. Hide the other sprites if needed
  or
  
• Put the sprite that you want to drag to the end of the sprite list. If you use clones, stop the project before dragging. (doesn't work when the bug below also happens)

Sprite hides and refuses to move (after dragging an overlapping part of another sprite)

• Drag the buggy sprite
  or
  
• Save and reload the project
  

Selection box is stuck on a vector shape

• Ctrl+A, Ctrl+X, go to another costume and back, select the buggy shape and deselect, Ctrl+V
  

——

Outdated workarounds:
Can't type text in the costume editor (fixed)

• Zoom in and click on the center of the text box
  or
  
• Press Tab and then Shift+Tab
  or
  
• Backpack text from another project and edit that

Some scripts become invisible while editing another sprite, but still run
This workaround doesn't work on the bug's current version.
Duplicating a block and removing the input of one of the copies sometimes causes an invisible bug in the sprite that leads to this.

• Download a copy of the project and see if it works. The missing code will probably show up.
  Don't use “Save as a copy” because that overwrites the original and there can be corrupting bugs, too

Code duplicates itself into other sprites (fixed)

• Don't use the dropdown to set the input of the

  point in direction (90)

  because that leads to this bug. Type in the number instead

Sprite only broadcast that doesn't work (fixed)
This happens with broadcasts made by adding scripts or sprites from the backpack, and those made by importing sprites. It can be caused by certain browser extensions, too.

• It can be fixed by replacing the broadcast with one that was made in the project

ForumBot wrote:

If I remember right, any ordinary Scratcher can make a sticky forum post by themselves. If the people over there want a sticky and find that it has enough information, then they will report it to be stickied. (I might be completely wrong in how that works though!)

“New message” / “Rename variable/list” popup hides instantly (touchscreen)

• Press the “new message”/“rename …” button longer
  or
  
• Move the block into a position where if you click the button, the popup will appear under your finger

Some scripts become invisible while editing another sprite, but still run
Duplicating a block and removing the input of one of the copies sometimes causes an invisible bug in the sprite that leads to this.

• Download a copy of the project and see if it works. The missing code will probably show up.
  Don't use “Save as a copy” because that overwrites the original and there can be corrupting bugs, too

^the version of the bug that used to be fixed by this doesn't occur anymore

Code duplicates itself into other sprites

• Don't use the dropdown to set the input of the

  point in direction (90)

  because that leads to this bug. Type in the number instead

^ seems to be fixed

Sprite only broadcast that doesn't work
This happens with broadcasts made by adding scripts or sprites from the backpack, and those made by importing sprites. It can be caused by certain browser extensions, too.

• It can be fixed by replacing the broadcast with one that was made in the project

^also fixed

Can't drag code into other sprites (touchscreen)

• Tap and hold the target sprite. With another finger, grab the blocks, and release them over the sprite list, but avoid touching the other sprites in the list. (also avoid touching backpack items)

Sprite hides and refuses to move (after dragging an overlapping part of another sprite)

• drag the buggy sprite
  or
  
• save and reload the project
  

Selection box is stuck on a vector shape

• Ctrl+A, Ctrl+X, go to another costume and back, select the buggy shape and deselect, Ctrl+V
  

Can't backpack blocks (touchscreen)

• Move the blocks over the sprite list and hold them. With another finger, tap and hold a point inside the backpack where it isn't covered by backpacked items, and release the blocks over the sprite list.