Lying on the back of the chair won't pull her stitches out. yes, she's fine with the current sweater and the cone. The stairs are She jumps from the books to the footstool, from the footstool to the chair and from the chair to the table. She does that instead of the stretching jump from the floor to the table, or the floor to the chair. "Stairs, steps" short jumps not long ones.
Truth: the vet should have told you, but probably didn't think to, but it takes a great deal of force to pull the stitches out. Vets don't pull the stitches out when they remove them, they cut the stitches then slip it out. I know you said she has dissolving stitches so you won't get to see him do that.
Here is another truth.
The time she is most likely to try to take the stitches out is when she's almost healed and they itch. At that point she will be sufficiently healed that the incision will stay closed and she will be fine.
Truth: the vet should have told you, but probably didn't think to, but it takes a great deal of force to pull the stitches out. Vets don't pull the stitches out when they remove them, they cut the stitches then slip it out. I know you said she has dissolving stitches so you won't get to see him do that.
Here is another truth.
The time she is most likely to try to take the stitches out is when she's almost healed and they itch. At that point she will be sufficiently healed that the incision will stay closed and she will be fine.