diff --git a/README.md b/README.md
index 9ce70f7f7..67ddaaeb5 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@ WYSIWYG.
 
 ### Free
 
-All local features are free.
+All local features are free, even for commercial use.
 
 * Content block
   * Block-level reference and two-way links
diff --git a/README_zh_CN.md b/README_zh_CN.md
index 3ecfb06fb..511aabded 100644
--- a/README_zh_CN.md
+++ b/README_zh_CN.md
@@ -27,7 +27,7 @@
 
 ### 免费
 
-所有本地功能都是免费的。
+所有本地功能都是免费的，即使是在商业环境下使用。
 
 * 内容块
   * 块级引用和双向链接
diff --git a/app/src/config/flashcard.ts b/app/src/config/flashcard.ts
index 5f83aa391..f3b4c34da 100644
--- a/app/src/config/flashcard.ts
+++ b/app/src/config/flashcard.ts
@@ -8,13 +8,13 @@ export const flashcard = {
         responsiveHTML = `<div class="b3-label">
     ${window.siyuan.languages.flashcardNewCardLimit}
     <div class="fn__hr"></div>
-    <input class="b3-text-field fn__flex-center fn__block" id="newCardLimit" step="1" min="1" type="number"${window.siyuan.config.flashcard.newCardLimit ? " checked" : "" } value="${window.siyuan.config.flashcard.newCardLimit}"/>
+    <input class="b3-text-field fn__flex-center fn__block" id="newCardLimit" step="1" min="0" type="number"${window.siyuan.config.flashcard.newCardLimit ? " checked" : "" } value="${window.siyuan.config.flashcard.newCardLimit}"/>
     <div class="b3-label__text">${window.siyuan.languages.flashcardNewCardLimitTip}</div>
 </div>
 <div class="b3-label">
     ${window.siyuan.languages.flashcardReviewCardLimit}
     <div class="fn__hr"></div>
-    <input class="b3-text-field fn__flex-center fn__block" id="reviewCardLimit" step="1" min="1" type="number"${window.siyuan.config.flashcard.reviewCardLimit ? " checked" : ""} value="${window.siyuan.config.flashcard.reviewCardLimit}"/>
+    <input class="b3-text-field fn__flex-center fn__block" id="reviewCardLimit" step="1" min="0" type="number"${window.siyuan.config.flashcard.reviewCardLimit ? " checked" : ""} value="${window.siyuan.config.flashcard.reviewCardLimit}"/>
     <div class="b3-label__text">${window.siyuan.languages.flashcardReviewCardLimitTip}</div>
 </div>`;
         /// #else
@@ -24,7 +24,7 @@ export const flashcard = {
         <div class="b3-label__text">${window.siyuan.languages.flashcardNewCardLimitTip}</div>
     </div>
     <span class="fn__space"></span>
-    <input class="b3-text-field fn__flex-center fn__size200" id="newCardLimit" step="1" min="1" type="number"${window.siyuan.config.flashcard.newCardLimit ? " checked" : "" } value="${window.siyuan.config.flashcard.newCardLimit}"/>
+    <input class="b3-text-field fn__flex-center fn__size200" id="newCardLimit" step="1" min="0" type="number"${window.siyuan.config.flashcard.newCardLimit ? " checked" : "" } value="${window.siyuan.config.flashcard.newCardLimit}"/>
 </label>
 <label class="fn__flex b3-label">
     <div class="fn__flex-1">
@@ -32,7 +32,7 @@ export const flashcard = {
         <div class="b3-label__text">${window.siyuan.languages.flashcardReviewCardLimitTip}</div>
     </div>
     <span class="fn__space"></span>
-    <input class="b3-text-field fn__flex-center fn__size200" id="reviewCardLimit" step="1" min="1" type="number"${window.siyuan.config.flashcard.reviewCardLimit ? " checked" : ""} value="${window.siyuan.config.flashcard.reviewCardLimit}"/>
+    <input class="b3-text-field fn__flex-center fn__size200" id="reviewCardLimit" step="1" min="0" type="number"${window.siyuan.config.flashcard.reviewCardLimit ? " checked" : ""} value="${window.siyuan.config.flashcard.reviewCardLimit}"/>
 </label>`;
         /// #endif
         return `${responsiveHTML}
diff --git a/kernel/api/setting.go b/kernel/api/setting.go
index 1f7d03610..a5c1594c3 100644
--- a/kernel/api/setting.go
+++ b/kernel/api/setting.go
@@ -95,12 +95,12 @@ func setFlashcard(c *gin.Context) {
 		return
 	}
 
-	if 1 > flashcard.NewCardLimit {
-		flashcard.NewCardLimit = 1
+	if 0 > flashcard.NewCardLimit {
+		flashcard.NewCardLimit = 20
 	}
 
-	if 1 > flashcard.ReviewCardLimit {
-		flashcard.ReviewCardLimit = 1
+	if 0 > flashcard.ReviewCardLimit {
+		flashcard.ReviewCardLimit = 200
 	}
 
 	model.Conf.Flashcard = flashcard
diff --git a/kernel/conf/export.go b/kernel/conf/export.go
index f63c7e43d..5b3773845 100644
--- a/kernel/conf/export.go
+++ b/kernel/conf/export.go
@@ -28,6 +28,7 @@ type Export struct {
 	FileAnnotationRefMode   int    `json:"fileAnnotationRefMode"`   // 文件标注引用导出模式，0：文件名 - 页码 - 锚文本，1：仅锚文本
 	PandocBin               string `json:"pandocBin"`               // Pandoc 可执行文件路径
 	MarkdownYFM             bool   `json:"markdownYFM"`             // Markdown 导出时是否添加 YAML Front Matter https://github.com/siyuan-note/siyuan/issues/7727
+	PDFFooter               string `json:"pdfFooter"`               // PDF 导出时页脚内容
 }
 
 func NewExport() *Export {
diff --git a/kernel/model/conf.go b/kernel/model/conf.go
index 2b0c3956e..38dbc8bcd 100644
--- a/kernel/model/conf.go
+++ b/kernel/model/conf.go
@@ -321,10 +321,10 @@ func InitConf() {
 	if nil == Conf.Flashcard {
 		Conf.Flashcard = conf.NewFlashcard()
 	}
-	if 1 > Conf.Flashcard.NewCardLimit {
+	if 0 > Conf.Flashcard.NewCardLimit {
 		Conf.Flashcard.NewCardLimit = 20
 	}
-	if 1 > Conf.Flashcard.ReviewCardLimit {
+	if 0 > Conf.Flashcard.ReviewCardLimit {
 		Conf.Flashcard.ReviewCardLimit = 200
 	}