Hi Tom,
This was an interesting exercise.
I tested it first and foremost on Chrome (as its the most commonly used) with browser set to 100% and display set at 100%, 125%, 150% and 175% and all worked seamlessly. There were no issues.
Firefox and Microsoft Edge however are another story.
With display at 175% & Firefox at 100% 1025px issue occurs & others appear ok
With display at 175% & MS Edge at 100% everything appears ok
With display at 150% & Firefox at 100% 1025px issue occurs & others appear ok
With display at 150% & MS Edge at 100% 1025px issue occurs & others appear ok
With display at 125% & Firefox at 100% 1025px issue occurs & others appear ok
With display at 125% & MS Edge at 100% everything appears ok
With display at 100% & Firefox at 100% everything appears ok
With display at 100% & MS Edge at 100% everything appears ok
Hope that helps to sort the bug(s)