[LyX/master] Fix C++20 warning on implicit capture of this via [=]

[Yuriy Skalko]

commit 3971b1b35ef6325b7816c77941d2d95bcc497417
Author: Yuriy Skalko <yuriy.skalko at gmail.com>
Date:   Mon Dec 28 20:59:48 2020 +0200

    Fix C++20 warning on implicit capture of this via [=]
---
 src/frontends/qt/GuiBibtex.cpp     |    2 +-
 src/frontends/qt/GuiCitation.cpp   |    2 +-
 src/frontends/qt/GuiDocument.cpp   |    2 +-
 src/frontends/qt/GuiLyXFiles.cpp   |    2 +-
 src/frontends/qt/GuiRef.cpp        |    2 +-
 src/graphics/GraphicsCacheItem.cpp |    2 +-
 src/insets/InsetExternal.cpp       |    2 +-
 src/insets/InsetInclude.cpp        |    4 ++--
 8 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/frontends/qt/GuiBibtex.cpp b/src/frontends/qt/GuiBibtex.cpp
index 66cff69..8d9e769 100644
--- a/src/frontends/qt/GuiBibtex.cpp
+++ b/src/frontends/qt/GuiBibtex.cpp
@@ -113,7 +113,7 @@ GuiBibtex::GuiBibtex(GuiView & lv)
 	        availableLV, SLOT(setFocus()));
 #else
 	connect(filter_, &FancyLineEdit::downPressed,
-	        availableLV, [=](){ focusAndHighlight(availableLV); });
+	        availableLV, [=, this](){ focusAndHighlight(availableLV); });
 #endif
 
 	availableLV->setToolTip(formatToolTip(qt_("This list consists of all databases that are indexed by LaTeX and thus are found without a file path. "
diff --git a/src/frontends/qt/GuiCitation.cpp b/src/frontends/qt/GuiCitation.cpp
index 20b4c34..1d89f20 100644
--- a/src/frontends/qt/GuiCitation.cpp
+++ b/src/frontends/qt/GuiCitation.cpp
@@ -157,7 +157,7 @@ GuiCitation::GuiCitation(GuiView & lv)
 	        availableLV, SLOT(setFocus()));
 #else
 	connect(filter_, &FancyLineEdit::downPressed,
-	        availableLV, [=](){ focusAndHighlight(availableLV); });
+	        availableLV, [=, this](){ focusAndHighlight(availableLV); });
 #endif
 	connect(regexp_, SIGNAL(triggered()),
 		this, SLOT(regexChanged()));
diff --git a/src/frontends/qt/GuiDocument.cpp b/src/frontends/qt/GuiDocument.cpp
index c21c3a0..4b9bdff 100644
--- a/src/frontends/qt/GuiDocument.cpp
+++ b/src/frontends/qt/GuiDocument.cpp
@@ -1673,7 +1673,7 @@ GuiDocument::GuiDocument(GuiView & lv)
 		modulesModule->availableLV, SLOT(setFocus()));
 #else
 	connect(filter_, &FancyLineEdit::downPressed,
-		modulesModule->availableLV, [=](){ focusAndHighlight(modulesModule->availableLV); });
+		modulesModule->availableLV, [=, this](){ focusAndHighlight(modulesModule->availableLV); });
 #endif
 
 
diff --git a/src/frontends/qt/GuiLyXFiles.cpp b/src/frontends/qt/GuiLyXFiles.cpp
index f14369a..7859d48 100644
--- a/src/frontends/qt/GuiLyXFiles.cpp
+++ b/src/frontends/qt/GuiLyXFiles.cpp
@@ -197,7 +197,7 @@ GuiLyXFiles::GuiLyXFiles(GuiView & lv)
 		filesLW, SLOT(setFocus()));
 #else
 	connect(filter_, &FancyLineEdit::downPressed,
-		filesLW, [=](){ focusAndHighlight(filesLW); });
+		filesLW, [=, this](){ focusAndHighlight(filesLW); });
 #endif
 
 	filterBarL->addWidget(filter_, 0);
diff --git a/src/frontends/qt/GuiRef.cpp b/src/frontends/qt/GuiRef.cpp
index f16c656..ccf2abf 100644
--- a/src/frontends/qt/GuiRef.cpp
+++ b/src/frontends/qt/GuiRef.cpp
@@ -67,7 +67,7 @@ GuiRef::GuiRef(GuiView & lv)
 	        refsTW, SLOT(setFocus()));
 #else
 	connect(filter_, &FancyLineEdit::downPressed,
-	        refsTW, [=](){ focusAndHighlight(refsTW); });
+	        refsTW, [=, this](){ focusAndHighlight(refsTW); });
 #endif
 
 	filterBarL->addWidget(filter_, 0);
diff --git a/src/graphics/GraphicsCacheItem.cpp b/src/graphics/GraphicsCacheItem.cpp
index 918dc02..49132cc 100644
--- a/src/graphics/GraphicsCacheItem.cpp
+++ b/src/graphics/GraphicsCacheItem.cpp
@@ -220,7 +220,7 @@ void CacheItem::Impl::startMonitor()
 		return;
 	monitor_ = FileSystemWatcher::activeMonitor(filename_);
 	// Disconnected at the same time as this is destroyed.
-	monitor_->connect([=](bool /* exists */){ startLoading(); });
+	monitor_->connect([this](bool /* exists */){ startLoading(); });
 }
 
 
diff --git a/src/insets/InsetExternal.cpp b/src/insets/InsetExternal.cpp
index 7575702..92308db 100644
--- a/src/insets/InsetExternal.cpp
+++ b/src/insets/InsetExternal.cpp
@@ -648,7 +648,7 @@ void InsetExternal::updatePreview() const
 		renderer_ = make_unique<RenderMonitoredPreview>(this);
 		RenderMonitoredPreview * preview_ptr = renderer_->asMonitoredPreview();
 		// This connection is closed at the same time as this is destroyed.
-		preview_ptr->connect([=]() { fileChanged(); });
+		preview_ptr->connect([this]() { fileChanged(); });
 		add_preview_and_start_loading(*preview_ptr, *this, buffer());
 		break;
 	}
diff --git a/src/insets/InsetInclude.cpp b/src/insets/InsetInclude.cpp
index ccee25f..71e9d38 100644
--- a/src/insets/InsetInclude.cpp
+++ b/src/insets/InsetInclude.cpp
@@ -185,7 +185,7 @@ InsetInclude::InsetInclude(Buffer * buf, InsetCommandParams const & p)
 	  set_label_(false), label_(nullptr), child_buffer_(nullptr), file_exist_(false),
 	  recursion_error_(false)
 {
-	preview_->connect([=](){ fileChanged(); });
+	preview_->connect([this](){ fileChanged(); });
 
 	if (isListings(params())) {
 		InsetListingsParams listing_params(to_utf8(p["lstparams"]));
@@ -201,7 +201,7 @@ InsetInclude::InsetInclude(InsetInclude const & other)
 	  set_label_(false), label_(nullptr), child_buffer_(nullptr), 
 	  file_exist_(other.file_exist_),recursion_error_(other.recursion_error_)
 {
-	preview_->connect([=](){ fileChanged(); });
+	preview_->connect([this](){ fileChanged(); });
 
 	if (other.label_)
 		label_ = new InsetLabel(*other.label_);