This is a behavior for official text plugin, or official sprite font plugin, or rex_tagtext plugin
Resize text object and background to show all lines (automatically or immediately)
Document, behavior and sample capx files are included.
- type something on text box.
Officially, text width and text height will be got at next tick after "action: set text" of text object , i.e. add a wait 0 action. This behavior could resize text / get text width immediately after "action: set text".