Small improvement

app/src/main/java/eu/faircode/email/EditTextCompose.java

@@ -75,7 +75,7 @@ public class EditTextCompose extends FixedEditText {
                         CharSequence text = item.getText();
                         if (text == null)
                             return false;
-                        html = "<div plain=\"true\">" + HtmlHelper.formatPre(text.toString()) + "</div>";
+                        html = "<div x-plain=\"true\">" + HtmlHelper.formatPre(text.toString()) + "</div>";
                     }
 
                     Document document = HtmlHelper.sanitizeCompose(context, html, false);

app/src/main/java/eu/faircode/email/FragmentMessages.java

@@ -5274,7 +5274,7 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
 
                                         // Write decrypted body
                                         String text = Helper.readText(plain);
-                                        String html = "<div plain=\"true\">" + HtmlHelper.formatPre(text) + "</div>";
+                                        String html = "<div x-plain=\"true\">" + HtmlHelper.formatPre(text) + "</div>";
                                         Helper.writeText(message.getFile(context), html);
                                         db.message().setMessageStored(message.id, new Date().getTime());
                                         db.message().setMessageFts(message.id, false);

app/src/main/java/eu/faircode/email/HtmlHelper.java

@@ -446,7 +446,7 @@ public class HtmlHelper {
                 .addAttributes(":all", "class")
                 .addAttributes(":all", "style")
                 .addAttributes("font", "size")
-                .addAttributes("div", "plain")
+                .addAttributes("div", "x-plain")
                 .removeTags("col", "colgroup", "thead", "tbody")
                 .removeAttributes("table", "width")
                 .removeAttributes("td", "colspan", "rowspan", "width")
@@ -732,7 +732,7 @@ public class HtmlHelper {
         for (Element pre : document.select("pre")) {
             pre.html(formatPre(pre.wholeText()));
             pre.tagName("div");
-            pre.attr("plain", "true");
+            pre.attr("x-plain", "true");
         }
 
         // Code
@@ -1789,7 +1789,7 @@ public class HtmlHelper {
                         block.add((TextNode) node);
                 } else if (node instanceof Element) {
                     element = (Element) node;
-                    if ("true".equals(element.attr("plain")))
+                    if ("true".equals(element.attr("x-plain")))
                         plain++;
                     if (BLOCK_START.contains(element.tagName())) {
                         normalizeText(block);
@@ -1802,7 +1802,7 @@ public class HtmlHelper {
             public void tail(Node node, int depth) {
                 if (node instanceof Element) {
                     element = (Element) node;
-                    if ("true".equals(element.attr("plain")))
+                    if ("true".equals(element.attr("x-plain")))
                         plain--;
                     if (BLOCK_END.contains(element.tagName())) {
                         normalizeText(block);

app/src/main/java/eu/faircode/email/MessageHelper.java

@@ -1591,7 +1591,7 @@ public class MessageHelper {
                 if (part.isMimeType("text/plain")) {
                     if ("flowed".equalsIgnoreCase(ct.getParameter("format")))
                         result = HtmlHelper.flow(result);
-                    result = "<div plain=\"true\">" + HtmlHelper.formatPre(result) + "</div>";
+                    result = "<div x-plain=\"true\">" + HtmlHelper.formatPre(result) + "</div>";
                 } else if (part.isMimeType("text/html")) {
                     if (TextUtils.isEmpty(charset)) {
                         // <meta charset="utf-8" />