There are 3 styles for image captions: left , center and right aligned
If you're using module "Photo" as standalone widget ( not inside the columns), the center aligned caption will have the following style:
The image can be fullwidth if you add class is-fullwidth as alternative text
The standalone module "Text with Photo" is the same like in any other Jimdo template, while inside the columns will have different style.
This is because of Play of Columns feature. For more details, please check this post
Standalone widget
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Module 'Text with Photo' inside the columns
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