same problem here.
screen freezes but the game seems to continue.
+ so far it happend in SO, ESO, a Corpus Spy mission and a grineer exterminate, login-screen
+ i only play in solo mode
+ it seems to have a 1/5 - 1/10 chance to occur in every missiontype
+ first happend after Wukong Prime: Hotfix 25.3.2 - July 12th
edit:
- https://digitalextremes.zendesk.com/hc/en-us/articles/212890418-What-should-I-do-if-my-game-keeps-crashing-
checked everything - it sadly did not change anything