Resizing and reordering execution specifications in sequence diagrams

In sequence diagrams, an execution specification automatically resizes vertically to indicate the time during which a participant is active. The top of the execution specification aligns at the point where the message is received and initiates the behavior; the bottom aligns with the finish of the behavior during an interaction. If you resize the execution occurrence across any messages and fragments, the execution specification reorders in the interaction.
You must have a sequence diagram open that contains at least one lifeline with an execution specification.
Restriction: You cannot resize an execution specification that has a return message attached to it.
To resize and reorder an execution specification, in the interaction frame, complete one of the following steps:
Note: If you reorder an execution occurrence and resize the execution specification upward, the start point of the execution specification appears before the message and fragments that you crossed. If you resize the execution specification downward, the finish point of the execution specification appears after the message and fragments that you crossed.
Related concepts
Execution specifications in sequence diagrams

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