Between the 47.4 and 47.5 releases, and between the 48.0 and 48.1 releases, we accidentally changed (emptied) a string in an attempt to fix an unrelated issue. We reverted this change quickly, but not before several languages pushed updated strings.
The string is “Search” in Keyboard → Custom Shortcuts → Launchers.
Please check if your language is now missing this string on the 47 or 48 branches. If so, you can probably reuse the string how it was before we accidentally changed it. The meaning and context of the string has not changed.