In Studio, the tab alignment button in View works only temporarily. The moment I scroll any, the source and target segments get out of whack. How can I get constant alignment once more?

Since I got the new Service Pack edition of Studio 2017, the source and target sides scroll independently without aligning, no matter how much I click on the tab alignment button in View! All that button does is align the two sides temporarily, whereas I almost always want them to stay aligned, or in fact ALWAYS want them aligned. What can I do?