Re-aquire first responder when necessary.

// FREEBIE

Signal/src/ViewControllers/ConversationView/ConversationInputToolbar.h

@@ -40,6 +40,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)beginEditingTextMessage;
 - (void)endEditingTextMessage;
+- (BOOL)isInputTextViewFirstResponder;
 
 - (void)setInputTextViewDelegate:(id<ConversationInputTextViewDelegate>)value;
 

Signal/src/ViewControllers/ConversationView/ConversationInputToolbar.m

@@ -240,6 +240,11 @@ static const CGFloat ConversationInputToolbarBorderViewHeight = 0.5;
     [self.inputTextView resignFirstResponder];
 }
 
+- (BOOL)isInputTextViewFirstResponder
+{
+    return self.inputTextView.isFirstResponder;
+}
+
 - (void)ensureContentConstraints
 {
     [NSLayoutConstraint deactivateConstraints:self.contentContraints];

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -1013,6 +1013,26 @@ typedef NS_ENUM(NSInteger, MessagesRangeSizeMode) {
 
     self.isViewCompletelyAppeared = YES;
     self.viewHasEverAppeared = YES;
+
+    // HACK: Because the inputToolbar is the inputAccessoryView, we make some special considertations WRT it's firstResponder status.
+    //
+    // When a view controller is presented, it is first responder. However if we resign first responder
+    // and the view re-appears, without being presented, the inputToolbar can become invisible.
+    // e.g. specifically works around the scenario:
+    // - Present this VC
+    // - Longpress on a message to show edit menu, which entails making the pressed view the first responder.
+    // - Begin presenting another view, e.g. swipe-left for details or swipe-right to go back, but quit part way, so that you remain on the conversation view
+    // - toolbar will be not be visible unless we reaquire first responder.
+    if (!self.isFirstResponder) {
+        
+        // We don't have to worry about the input toolbar being visible if the inputToolbar.textView is first responder
+        // In fact doing so would unnecessarily dismiss the keyboard which is probably not desirable and at least
+        // a distracting animation.
+        if (!self.inputToolbar.isInputTextViewFirstResponder) {
+            DDLogDebug(@"%@ reclaiming first responder to ensure toolbar is shown.", self.logTag);
+            [self becomeFirstResponder];
+        }
+    }
 }
 
 // `viewWillDisappear` is called whenever the view *starts* to disappear,