This is weird to my understanding and I am sure I am missing something here...
Also, GitKraken is splitting/showing commits of same branch as 2 different branches.
Here an example:
Note: numbers represents chronological order when commits were created. All commits in below picture are from master branch. Commit 7 parent is commit 6.
In GitHub and gitk I see only one branch with all commits in chronological order.
Edit with gitk --all: (sorry for trimming message info). As I said, in github commits also are shown in chronological "expected" order.
I asked GitKraken support about this a while ago. Their response:
The graph behavior you noted below is a known issue that is currently with our team for review. GitKraken only looks at the commit timestamp when drawing the graph, so when those commits are not in chronological order, the result is the orphaned commit seemingly on a separate branch. I'll give that existing item a +1 to note your additional interest in a fix for that issue.