fixup! Tor Browser strings

Bug 41814: Use "Tor bridge" instead of "vanilla bridge".

browser/locales/en-US/browser/tor-browser.ftl

@@ -82,6 +82,8 @@ tor-bridges-built-in-status-connected = Connected
 # Shown at the start of a Tor bridge line.
 # $type (String) - The Tor bridge type ("snowflake", "obfs4", "meek-azure").
 tor-bridges-type-prefix = { $type } bridge:
+# Shown at the start of a Tor bridge line, when the transport type is unknown (or "vanilla").
+tor-bridges-type-prefix-generic = Tor bridge:
 # The name and accessible description for a bridge emoji cell. Each bridge address can be hashed into four emojis shown to the user (bridgemoji feature). This cell corresponds to a *single* such emoji. The "title" should just be emojiName. The "aria-description" should give screen reader users enough of a hint that the cell contains a single emoji.
 # $emojiName (String) - The name of the emoji, already localized.
 # E.g. with Orca screen reader in en-US this would read "unicorn. Row 2 Column 2. Emoji".