diff --git a/lib/Epub/Epub/blocks/TextBlock.cpp b/lib/Epub/Epub/blocks/TextBlock.cpp
index a9fefb25..3549087e 100644
--- a/lib/Epub/Epub/blocks/TextBlock.cpp
+++ b/lib/Epub/Epub/blocks/TextBlock.cpp
@@ -19,6 +19,7 @@ void TextBlock::render(const GfxRenderer& renderer, const int fontId, const int
     return;
   }
 
+  const bool scanning = renderer.isFontCacheScanning();
   const int ascender = renderer.getFontAscenderSize(fontId);
   for (size_t i = 0; i < words.size(); i++) {
     const int wordX = wordXpos[i] + x;
@@ -58,7 +59,7 @@ void TextBlock::render(const GfxRenderer& renderer, const int fontId, const int
       renderer.drawText(fontId, wordX, wordY, words[i].c_str(), true, currentStyle, baseDir);
     }
 
-    if ((currentStyle & EpdFontFamily::UNDERLINE) != 0) {
+    if (!scanning && (currentStyle & EpdFontFamily::UNDERLINE) != 0) {
       const std::string& w = words[i];
       const int fullWordWidth = renderer.getTextWidth(fontId, w.c_str(), currentStyle, baseDir);
       // y is the top of the text line; add ascender to reach baseline, then offset 2px below
diff --git a/lib/GfxRenderer/GfxRenderer.cpp b/lib/GfxRenderer/GfxRenderer.cpp
index e5246a07..759b2ad4 100644
--- a/lib/GfxRenderer/GfxRenderer.cpp
+++ b/lib/GfxRenderer/GfxRenderer.cpp
@@ -91,6 +91,8 @@ void GfxRenderer::begin() {
   bwBufferChunks.assign((frameBufferSize + BW_BUFFER_CHUNK_SIZE - 1) / BW_BUFFER_CHUNK_SIZE, nullptr);
 }
 
+bool GfxRenderer::isFontCacheScanning() const { return fontCacheManager_ && fontCacheManager_->isScanning(); }
+
 void GfxRenderer::insertFont(const int fontId, EpdFontFamily font) {
   auto result = fontMap.insert({fontId, font});
   if (!result.second) {
diff --git a/lib/GfxRenderer/GfxRenderer.h b/lib/GfxRenderer/GfxRenderer.h
index 16aa6de9..924e5c0b 100644
--- a/lib/GfxRenderer/GfxRenderer.h
+++ b/lib/GfxRenderer/GfxRenderer.h
@@ -104,6 +104,7 @@ class GfxRenderer {
   }
   void setFontCacheManager(FontCacheManager* m) { fontCacheManager_ = m; }
   FontCacheManager* getFontCacheManager() const { return fontCacheManager_; }
+  bool isFontCacheScanning() const;
   const std::map<int, EpdFontFamily>& getFontMap() const { return fontMap; }
   void registerSdCardFont(int fontId, SdCardFont* font) { sdCardFonts_[fontId] = font; }
   void unregisterSdCardFont(int fontId) { removeFont(fontId); }