Re: [stable build from source] Ubuntu 20.04 scintilla not found

In my build on Ubuntu 20.04, it seems from the config.log file that
scintilla was at first not found, but then was found:

configure:70459: checking for the QScintilla library for Qt 5
configure:70504: g++ -o conftest -fPIC -g -O2 -pthread -fopenmp
-I/usr/include/x86_64-linux-gnu/qt5/QtNetwork
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtPrintSupport
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtHelp
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtWidgets
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtGui
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtSql
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtXml
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtCore
-I/usr/include/x86_64-linux-gnu/qt5 -fPIC -I/usr/include/suitesparse
conftest.cpp -lQt5Network -lQt5PrintSupport -lQt5Help -lQt5Widgets
-lQt5Gui -lQt5Sql -lQt5Xml -lQt5Core -lqscintilla2-qt5 >&5
/usr/bin/ld: cannot find -lqscintilla2-qt5
collect2: error: ld returned 1 exit status
...
configure:70504: g++ -o conftest -fPIC -g -O2 -pthread -fopenmp
-I/usr/include/x86_64-linux-gnu/qt5/QtNetwork
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtPrintSupport
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtHelp
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtWidgets
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtGui
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtSql
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtXml
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtCore
-I/usr/include/x86_64-linux-gnu/qt5 -fPIC -I/usr/include/suitesparse
conftest.cpp -lQt5Network -lQt5PrintSupport -lQt5Help -lQt5Widgets
-lQt5Gui -lQt5Sql -lQt5Xml -lQt5Core -lqscintilla2_qt5 >&5
configure:70504: $? = 0
configure:70527: result: -lqscintilla2_qt5
configure:70537: checking whether QScintilla has version 2.6.0 or later
configure:70575: g++ -E -I/usr/include/x86_64-linux-gnu/qt5/QtNetwork
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtPrintSupport
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtHelp
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtWidgets
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtGui
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtSql
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtXml
-I/usr/include/x86_64-linux-gnu/qt5
-I/usr/include/x86_64-linux-gnu/qt5/QtCore
-I/usr/include/x86_64-linux-gnu/qt5 -fPIC -I/usr/include/suitesparse
conftest.cpp
configure:70575: $? = 0
configure:70590: result: yes
...
| #define HAVE_QT 1
| #define HAVE_QSTANDARDPATHS 1
| #define HAVE_QGUIAPPLICATION_SETDESKTOPFILENAME 1
| #define HAVE_QHELPSEARCHQUERYWIDGET_SEARCHINPUT 1
| #define HAVE_QSCREEN_DEVICEPIXELRATIO 1
| #define HAVE_QOPENGLWIDGET 1
| #define HAVE_QGLWIDGET 1
| #define HAVE_QT_GRAPHICS 1
| #define HAVE_QOFFSCREENSURFACE 1
| #define HAVE_QT_OFFSCREEN 1
| #define HAVE_QSCI_VERSION_2_6_0 1
| #define HAVE_QSCINTILLA 1
| #define HAVE_QSCI_QSCILEXEROCTAVE_H 1
| #define HAVE_QSCI_QSCILEXERMATLAB_H 1
| #define HAVE_QT5 1