Elastic: Fix text selection with Shift+PageUp and Shift+PageDown in plain text editor when using Chrome (#7230)

CHANGELOG

@@ -15,6 +15,7 @@ CHANGELOG Roundcube Webmail
 - Fix so messages in threads with no root aren't displayed separately (#4999)
 - Fix bug where attachments with Content-Id were attached to the message on reply (#7122)
 - Fix identity selection on reply when both sender and recipient addresses are included in identities (#7211)
+- Elastic: Fix text selection with Shift+PageUp and Shift+PageDown in plain text editor when using Chrome (#7230)
 
 RELEASE 1.4.3
 -------------

program/js/editor.js

@@ -331,7 +331,7 @@ function rcube_text_editor(config, id)
         if (is_sig)
           data = data.replace(sig_mark, "\n" + signature.text);
 
-        input.val(data).focus();
+        input.val(data).focus().trigger('input');
         rcmail.set_caret_pos(input.get(0), 0);
       };
 

skins/elastic/styles/widgets/editor.less

@@ -898,6 +898,7 @@ html.touch .mce-grid td {
         font-family: monospace;
         width: 100% !important;
         padding-top: 2.5rem;
+        resize: none;
     }
 
     & > iframe { // e.g. mailvelope frame

skins/elastic/ui.js

@@ -3741,37 +3741,20 @@ function rcube_elastic_ui()
      */
     function textarea_autoresize_init(textarea)
     {
-        var resize = function(e) {
-            clearTimeout(env.textarea_timer);
-            env.textarea_timer = setTimeout(function() {
-                var area = $(e.target),
-                    initial_height = area.data('initial-height'),
-                    scroll_height = area[0].scrollHeight;
-
-                // do nothing when the area is hidden
-                if (!scroll_height) {
-                    return;
-                }
-
-                if (!initial_height) {
-                    area.data('initial-height', initial_height = scroll_height);
-                }
-
-                // strange effect in Chrome/Firefox when you delete a line in the textarea
-                // the scrollHeight is not decreased by the line height, but by 2px
-                // so jumps up many times in small steps, we'd rather use one big step
-                if (area.outerHeight() - scroll_height == 2) {
-                    scroll_height -= 19; // 21px is the assumed line height
+        // FIXME: Is there a better way to get initial height of the textarea?
+        var min_height = ($(textarea)[0].rows || 5) * 21,
+            resize = function(e) {
+                var oldHeight = $(this).outerHeight();
+                $(this).outerHeight(0);
+                var newHeight = Math.max(min_height, this.scrollHeight);
+                $(this).outerHeight(oldHeight);
+
+                if (newHeight !== oldHeight) {
+                    $(this).height(newHeight);
                 }
+            };
 
-                area.outerHeight(Math.max(initial_height, scroll_height));
-            }, 10);
-        };
-
-        $(textarea).css('overflow-y', 'hidden').on('input', resize).trigger('input');
-
-        // Make sure the height is up-to-date also in time intervals
-        setInterval(function() { $(textarea).trigger('input'); }, 1000);
+        $(textarea).on('input', resize).trigger('input');
     };
 
     // Inititalizes smart list input