fix: some UI issues

frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/copy_and_paste/paste_from_plain_text.dart

@@ -73,8 +73,10 @@ extension PasteFromPlainText on EditorState {
   }
 
   void checkToShowPasteAsMenu(Node node) {
+    if (selection == null || !selection!.isCollapsed) return;
+    if (UniversalPlatform.isMobile) return;
     final href = _getLinkFromNode(node);
-    if (href != null && !UniversalPlatform.isMobile) {
+    if (href != null) {
       final context = document.root.context;
       if (context != null && context.mounted) {
         PasteAsMenuService(context: context, editorState: this).show(href);

frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/link_embed/link_embed_block_component.dart

@@ -64,10 +64,10 @@ class LinkEmbedBlockComponentState extends State<LinkEmbedBlockComponent>
     parser.addLinkInfoListener((v) {
       if (mounted) {
         setState(() {
-          linkInfo = v;
+          if (v.isEmpty() && linkInfo.isEmpty()) {
-          if (v.isEmpty()) {
             status = EmbedLoadingStatus.error;
           } else {
+            linkInfo = v;
             status = EmbedLoadingStatus.idle;
           }
         });
@@ -197,27 +197,29 @@ class LinkEmbedBlockComponentState extends State<LinkEmbedBlockComponent>
                 ),
               ),
               HSpace(12),
-              Column(
+              Expanded(
-                crossAxisAlignment: CrossAxisAlignment.start,
+                child: Column(
-                mainAxisSize: MainAxisSize.min,
+                  crossAxisAlignment: CrossAxisAlignment.start,
-                children: [
+                  mainAxisSize: MainAxisSize.min,
-                  FlowyText(
+                  children: [
-                    linkInfo.siteName ?? '',
+                    FlowyText(
-                    color: textScheme.primary,
+                      linkInfo.siteName ?? '',
-                    fontSize: 14,
+                      color: textScheme.primary,
-                    figmaLineHeight: 20,
+                      fontSize: 14,
-                    fontWeight: FontWeight.w600,
+                      figmaLineHeight: 20,
-                    overflow: TextOverflow.ellipsis,
+                      fontWeight: FontWeight.w600,
-                  ),
+                      overflow: TextOverflow.ellipsis,
-                  VSpace(4),
+                    ),
-                  FlowyText.regular(
+                    VSpace(4),
-                    url,
+                    FlowyText.regular(
-                    color: textScheme.secondary,
+                      url,
-                    fontSize: 12,
+                      color: textScheme.secondary,
-                    figmaLineHeight: 16,
+                      fontSize: 12,
-                    overflow: TextOverflow.ellipsis,
+                      figmaLineHeight: 16,
-                  ),
+                      overflow: TextOverflow.ellipsis,
-                ],
+                    ),
+                  ],
+                ),
               ),
             ],
           ),

frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/link_preview/custom_link_parser.dart

@@ -32,11 +32,12 @@ class LinkParser {
         imageUrl: previewData.image?.url,
         faviconUrl: favicon?.url,
       );
-      await _cache.set(url, linkInfo);
+      if (!linkInfo.isEmpty()) await _cache.set(url, linkInfo);
       refreshLinkInfo(linkInfo);
       return linkInfo;
     } catch (e, s) {
       Log.error('get link info error: ', e, s);
+      refreshLinkInfo(LinkInfo());
       return null;
     }
   }
@@ -99,6 +100,7 @@ class LinkInfo {
       return FlowyNetworkSvg(
         iconUrl,
         height: size.height,
+        width: size.width,
         errorWidget: const FlowySvg(FlowySvgs.toolbar_link_earth_m),
       );
     }
@@ -106,6 +108,7 @@ class LinkInfo {
       url: iconUrl,
       fit: BoxFit.contain,
       height: size.height,
+      width: size.width,
       errorWidgetBuilder: (context, error, stackTrace) =>
           const FlowySvg(FlowySvgs.toolbar_link_earth_m),
     );

frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/mention/mention_link_block.dart

@@ -43,7 +43,7 @@ class _MentionLinkBlockState extends State<MentionLinkBlock> {
   final parser = LinkParser();
   _LoadingStatus status = _LoadingStatus.loading;
   final previewController = PopoverController();
-  LinkInfo? linkInfo;
+  LinkInfo linkInfo = LinkInfo();
   bool isHovering = false;
   int previewFocusNum = 0;
   bool isPreviewHovering = false;
@@ -60,7 +60,7 @@ class _MentionLinkBlockState extends State<MentionLinkBlock> {
   int get index => widget.index;
 
   bool get readyForPreview =>
-      status == _LoadingStatus.idle && !(linkInfo?.isEmpty() ?? true);
+      status == _LoadingStatus.idle && !linkInfo.isEmpty();
 
   @override
   void initState() {
@@ -69,10 +69,10 @@ class _MentionLinkBlockState extends State<MentionLinkBlock> {
     parser.addLinkInfoListener((v) {
       if (mounted) {
         setState(() {
-          linkInfo = v;
+          if (v.isEmpty() && linkInfo.isEmpty()) {
-          if (v.isEmpty()) {
             status = _LoadingStatus.error;
           } else {
+            linkInfo = v;
             status = _LoadingStatus.idle;
           }
         });
@@ -112,7 +112,7 @@ class _MentionLinkBlockState extends State<MentionLinkBlock> {
       borderRadius: BorderRadius.circular(16),
       popupBuilder: (context) => readyForPreview
           ? MentionLinkPreview(
-              linkInfo: linkInfo ?? LinkInfo(),
+              linkInfo: linkInfo,
               showAtBottom: showAtBottom,
               triggerSize: getSizeFromKey(),
               onEnter: (e) {
@@ -170,7 +170,7 @@ class _MentionLinkBlockState extends State<MentionLinkBlock> {
               HSpace(4),
               Flexible(
                 child: FlowyText(
-                  linkInfo?.siteName ?? url,
+                  linkInfo.siteName ?? url,
                   color: theme.textColorScheme.primary,
                   fontSize: 14,
                   figmaLineHeight: 20,
@@ -194,7 +194,7 @@ class _MentionLinkBlockState extends State<MentionLinkBlock> {
         child: const CircularProgressIndicator(strokeWidth: 1),
       );
     } else {
-      icon = linkInfo?.buildIconWidget() ?? defaultWidget;
+      icon = linkInfo.buildIconWidget();
     }
     return SizedBox(
       height: 20,