משתנה placeholder שניתן לעריכה

Edit the name of this PROJECT_ID.

This example adds the `readonly` class to the <var> element to create an
UNEDITABLE_VARIABLE.

This example adds the `readonly` class to the code block to disable editability
of both VARIABLE_1 and VARIABLE_2.

This EDITABLE variable has a tooltip that defaults to the
name of its original placeholder text.

This EDITABLE variable uses a `label`
attribute to create a custom tooltip named
Edit me.

This variable synchronizes by default because it is in a click-to-copy code
block. It has a `label` attribute named `variable with scope`:
  VARIABLE

This variable adds the `no-scope` class so that it does not synchronize with the
other variables and has a `label` attribute named `variable without scope`:
  VARIABLE

This variable also synchronizes by default and has a `label` attribute named
`variable with scope`:
  VARIABLE