There is a significant textual; variation between TR, Byzantine text, the Majority text, and NA28/UBS5 which I document in the table below. It all concerns the instruction to John at the opening of each seal; whether to simple "Come" or "Come and see".
Rev 6 |
NA28/UBS5 |
Byzantine Text |
Majority Text |
TR |
V1 |
"Come" |
"Come and see" |
"Come and see" |
"Come and look" |
V3 |
"Come" |
"Come" |
"Come" |
"Come and look" |
V5 |
"Come" |
"Come and see" |
"Come and see" |
"Come and look" |
V7 |
"Come" |
"Come and see" |
"Come and see" |
"Come and look" |
At least the NA28/UBS5 text is consistent (as is the TR). Now, we observe two more things about what happens in the vision. The OP asks about what John saw - he explicitly says what he say because after each instruction by one of the living creatures he exclaims: "I looked and behold I saw a horse ..."
That is, John did NOT read the scroll - he could not read the scroll because until all seven seals were broken, it could not be unrolled!
Thus, what John saw was NOT the writing on the scroll but the horse and its rider which in each case he proceeds to describe.