Search: Cannot navigate back to previous history entry

[mootari]

Describe the bug

To Reproduce

1. Open https://observablehq.com/
2. Enter "foo" in the search bar and press Return.
3. Change the search term to "bar". Either press Return or wait 1-2 seconds.
4. Attempt to navigate to the previous page via the browser's back button.
5. Attempt to navigate back by explicitely selecting an earlier search page entry in the history.

In both attempts the previous page content will be visible for a split second, immediately followed by a redirect to the most recent query.

[mootari]

Workaround: Opening the previous page in a new tab (e.g. by cmd+clicking the back button) will prevent the route change.