If you play different versions you notice that it happens often.
Most time talent tree is green square but works normally when you click it (when you play 7.00 version). Sometimes when you play new version its green square but inside is green square too but you can still select. Yesterday played and for 1 guy didnt work at all, he couldnt even select talent.
Dont think dota loads something inside that file because for me it has date modified 02.09.21 and talents were broken and normal for me after that date randomly