5.2.1
Fixed a bug in Pulldown format questions where only one Pulldown exists and the correct answer has more than two letters.
Adjusted the size of the image before enlargement in Photoswipe / Fixed the width 270 to enlarge up to 600 pixels depending on the screen size
Fixed a bug that the counter stops after the first question is answered when "question" is not specified in the option "count_down_mode".
Fixed an issue with button formatting where HTML tags such as image tags would not work correctly when specified as choices.
