Activate the ability to add topic number in captions.
In the image below, the option is activated, and the caption displays the number of the topic (2.1), which is separated from the serial number (1) by the symbol "—" (long dash)
Activated when the option Add topic number is enabled.
The image below demonstrates a caption text when "Hide delimiter at the end of the topic number" checkbox is not set and a topic number has a delimiter "." (dot).
The numbering of an image or a table displays the ordinal number of an object. By default, Continuous numbering is selected — this is the numbering of objects in order, sequentially, incrementally without gaps, not affected by topic's level.