Baal Haturim explains that Moshe's Delayed return is compared to Sisra's delayed return. Since Sisra was dead and the Jews thought that Moshe too was dead. The Zohar sheds light on why Sisra's mother was looking out the 'window'. There is a deeper meaning to Yaakov appearing to Yosef in the 'window.'

Sources

Shemos Perek 32 Possuk 1

Commentary of Rashi on Possuk

Baal Haturim on the Possuk

Shoftim Perek 5 Possuk 28

Commentary of Zohar on the Possuk

Commentary of Rashi on Bereishis Perek 39 Possuk 1

Gemara Rosh Hashana 33 B

Gemara South 36 B