Overview of the Issue
When upgrading to WPML 3.7.0, translations of strings wrapped in the wpml-string shortcodes are lost.
Workaround
This issue is fixed in WPML String Translation 2.5.4. Updating solves it on your site, so you only need this workaround if you can’t update yet.
Apply the following patch in the ../wpml-string-translation/inc/wpml-string-shortcode.php file, on line 8:
Replace:
$atts = shortcode_atts( array(), $atts );
With:
extract( shortcode_atts( array(), $atts ) );