colour markers by:

• year
• month
• year+month
• nothing

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filter by dates (click to expand):

	01	02	03	04	05	06	07	08	09	10	11	12
2012	01	02	03	04	05	06	07	08	09	10	11	12
2015	01	02	03	04	05	06	07	08	09	10	11	12
2017	01	02	03	04	05	06	07	08	09	10	11	12
2022	01	02	03	04	05	06	07	08	09	10	11	12

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