[Reg 14.0.0 -> 16.0.1] Excessively large auto-indentation in complex *.js files

Steps to reproduce

1. Download the attached sample file
2. In Qt Creator, select "Open File or Project..." and select the downloaded file without loading any project
3. Select all the content (Ctrl+A)
4. Unindent the whole file (press Shift+Tab repeatedly)
5. Auto-indent the whole file (Ctrl+I)

Outcomes
Each "step" of the indentation is huge:

Observations

• Enabling or disabling "Auto detect" doesn't seem to have an effect
• If I copy the whole file's contents and paste them inline into a *.qml file, the auto-indentation becomes a lot more sensible