Found the following hamletworks.org entries referring to line 1342-3

View Commentary Note for 1340-2
1340-1 Ham. I will tell you why, so shall my anticipation | preuent your  
1341-2 discouery, {and} <of> your secrecie to the King & | Queene moult no fea- 

View Material Textual Note for 1340-2
1340-1 Ham. I will tell you why, so shall my anticipation | preuent your  
1341-2 discouery, {and} <of> your secrecie to the King & | Queene moult no fea- 

View Commentary Note for 1342-3
1342-3 ther, I haue of late, but wherefore | I knowe not, lost all my mirth, 

View Material Textual Note for 1342-3
1342-3 ther, I haue of late, but wherefore | I knowe not, lost all my mirth,