NPE:
Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
at javafx.controls/com.sun.javafx.scene.control.behavior.TableViewBehaviorBase.activate(TableViewBehaviorBase.java:890)
at javafx.controls/com.sun.javafx.scene.control.inputmap.InputMap.handle(InputMap.java:274)

The line of code is:
boolean isEditable = isControlEditable() && cell.getTableColumn().isEditable();

Based on earlier code, the cell.getTableColumn() call is returning null in some cases.

This only occurs in an uncommon situation, so it isn't high priority, but is an easy fix nonetheless.