My apologies to you with my quoted comment "no business being on the roof"
I understand You need to get some jobs done and concerned about the safety factors, and it is good for you to ask

it's just that over the past 30+ years of me hiring guys that tell me they have no problems with working on ladders scaffolds etc, only to get the job and once they are on a ladder they freeze and are scared to death, Heck one time I had to call a boom truck to get one of my best employ down from the top of a chimney chase approx 60ft high took a 40 ft ladder plus 2 scaffold

so freezing up can happen to the best of us, Some people say that being scared is only natural, although in my business you cannot be afraid of hights, if so it will get you hurt or killed, I'm not saying you don't need to maintain a safety factor of concern and safety environment using good safe tools,Oh! and (common since).........
in construction you have 3 types of people,
1-Cautious/Careful,- be sure all safety measures are in place before working.
2-stupid/Careless, - ones who cut their fingers off & fall from ladders
3-people with common since that know when Not! to try something their not sure they can do, .....and to me these are the smartest groups

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Now preaching over..
There is another device I use on ladders when working around windows
its called a window standoff, in your picture it looks like you have a standard 12" soffit overhang with gutters, obviously you dont want to prop a ladder on the gutter, so any of these devices metioned will work either on the roof or against the wall, But when installing it bring it down to the 2nd or 3rd rung this way you'll have enough ladder above the roof to grab hold to when attempting to step back onto the ladder,