…hat let the user set a log file name, whether to include a stack trace, and the truncation lengths for strings and arrays.

- Tweaked the style of repeatable buttons and dash-icon buttons for WordPress 5.3 or above.
- Changed the form nonce lifespan to 2 days from 1 hour.
- Changed the `id` attribute of internal styles and scripts to be all lower-cased.
- Fixed a bug with the `select2` custom field type that repeated select2 field was not selectable.
- Fixed a bug that some internal styles were not minified when the site debug mode is turned off.
- Fixed a bug that same values of internal styles and scripts with the `style_{extended class name}`, `style_ie_{extended class name}` and `script_{extended class name}` were inserted multiple times.
- Fixed a bug that the collapsible section toggle icons were not toggled.
- Fixed a bug that in `admin-ajax.php` unnecessary callbacks were loaded.
- Deprecated debug information for section and field arguments.