This appears to mostly be a visualization bug, but it makes it impossible to tell which drawers are linked to the controller and which ones are not.

Mod version 1.18.2.0.0.17
Modpack: All The Mods 7

Observed behavior: After attempting to use the multiple add mode with the Linking Tool to add multiple drawers to the controller, the Linking Tool now permanently shows the selection outline box at all times when held in the main hand. Have logged out and back in. Have changed dimensions and returned. Neither has had any effect on the issue. This means I can no longer see what drawers are and are not connected to the controller.

Screenshot 1

Screenshot 2

Also tried breaking and replacing the controller block, and the problem persists.

I believe I figured out the cause of this issue, and it's an order of operations problem. While using the linking tool set to "Select Multiple", it did not register that I had right clicked on a second block for the selection area. This leaves the selection area rendering; if you then change the mode of the linking tool to Select Single, it allows you to do so, but leaves the multiple block selection area rendering as shown above. You have to go back to Select Multiple, and then successfully select a beginning and end block to stop the selection box from rendering.

Suggestion: When the mode changes from Select Multiple to Select Single, stop rendering the multi-select box if it is active.

Alternate suggestion: (This may be easier code wise, but not a great UX) Do not allow the player to change the mode of the linking tool if a multi-select is in progress.