When opening a record (entity or transaction), it's always the first tab that is opened by default. To set another tab as the default tab, please follow the steps below.
1. Navigate to Customization > Forms > select Transaction Forms or Entity Forms.
2. Edit the preferred form.
3. Under Tabs, move the tab you want to set as default tab to be opened when the record is opened to the top of the list. Or click Move to Top once selected.
4. Click Save.