The Options Panel is available in the Sequence View and in the Assembly Browser. By default, it is closed. To open a tab of the Options Panel click on the corresponding icon at the right side of a Sequence View or Assembly Browser window. To close the tab click again on the tab icon.
Note that Ctrl key can be used to open several tabs at the same time. In this case the tabs are shown on the Options Panel one after another.
More detailed information about different Options Panel tabs can be found in the following chapters:
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