Odoo does not provide a built-in Month-Year picker for fields.Date; a date field always requires a complete date value, including the day. While it may be possible to customize the date picker to display only months and years, support varies depending on the Odoo version and widget implementation. For a reliable solution, it is generally recommended to use separate fields for Month and Year, or implement a custom widget if a true Month-Year selection interface is required. This approach provides better control and compatibility across Odoo versions.

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