Repl is updating source slow - whats best practice?

if i my repl - code it shows often the old version of the code
Then i easily see that is slow and i not so confused ( Example where you could easily see its runs the old version as screenshot below ).
More difficult is it if it not run the new version of a source (technically the same).
Sometimes then its much more difficult to recognizance that its not my mistake.
That could make confusing my.

Often then i send a question to the forum go for coffee but when i back then problem is solved like magic.

What could be a best practice? What could we do? How could i not so much confused by testing with repl? Are there special reasons? Is it better to work local? How? Should there be warnings in the tasks? Warnings at the reptl GUI?
Is a slow and bad internet connection maybe a reason?

Thanks for think about this