Index: sbbs.el
==================================================================
--- sbbs.el
+++ sbbs.el
@@ -53,10 +53,15 @@
 (defface sbbs--spoiler-face
   '((((background light)) :background "black" :foreground "black")
     (((background dark)) :background "white" :foreground "white"))
   "Face for spoiler text in threads.")
 
+(defface sbbs--uncover-spoiler-face
+  '((((background light)) :background "black" :foreground "white")
+    (((background dark)) :background "white" :foreground "black"))
+  "Face for spoiler text in threads.")
+
 (defface sbbs--code-face
   '((((background light)) :background "gray89")
     (((background dark)) :background "gray11"))
   "Face for code blocks in threads.")
 
@@ -72,10 +77,13 @@
 
 Used in thread and reply buffers.")
 
 (defvar-local sbbs--limit-stack nil
   "Stack of last limit specs.")
+
+(defvar-local sbbs--last-spoiler nil
+  "Point of last spoiler visited.")
 
  ;; BOARD OBJECT AND FUNCTIONS
 
 (defun sbbs-make-board (domain name &optional tls)
   "Create board object, using DOMAIN, NAME and TLS flag."
@@ -309,10 +317,25 @@
     (add-text-properties start (1- (point)) '(face highlight))
     (set-text-properties (1- (point)) (point) nil)
     (sbbs--insert-sxml (cdr (assq 'content (cdr post))))
     (add-text-properties start (point) (list 'sbbs-thread-nr (car post)))))
 
+(defun sbbs--uncover-spoiler ()
+  ""
+  (cond ((eq (get-text-property (point) 'face) 'sbbs--spoiler-face)
+         (let* ((start (previous-property-change (1+ (point))))
+               (end (next-property-change (point)))
+               (o (make-overlay start end (current-buffer) t t)))
+           (overlay-put o 'face 'sbbs--uncover-spoiler-face)
+           (overlay-put o 'sbbs-uncover-p t))
+         (setq sbbs--last-spoiler (point)))
+        (sbbs--last-spoiler
+         (dolist (o (overlays-at sbbs--last-spoiler))
+           (when (overlay-get o 'sbbs-uncover-p)
+             (delete-overlay o)))
+         (setq sbbs--last-spoiler nil))))
+
  ;; URL.EL CALLBACKS
 
 (defun sbbs--board-loader (status buf)
   "Callback function for `url-retrieve' when loading board.
 
@@ -574,11 +597,13 @@
 
 (define-derived-mode sbbs-read-mode special-mode "SchemeBBS Read"
   "Major mode for reading a thread."
   (buffer-disable-undo)
   (visual-line-mode t)
-  (setq-local revert-buffer-function #'sbbs--reload-thread))
+  (setq-local revert-buffer-function #'sbbs--reload-thread)
+  (add-hook 'post-command-hook #'sbbs--uncover-spoiler
+            nil t))
 
 (defvar sbbs-compose-mode-map
   (let ((map (make-sparse-keymap)))
     (define-key map (kbd "C-c C-c") #'sbbs-compose-create)
     map))