diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -62,7 +62,6 @@
     CoreAddons
     DocTools
     I18n
-    KHtml
     Parts
     Plotting
     Solid
@@ -74,7 +73,7 @@
     VARIABLE_PREFIX KALZIUMLIB
 )
 
-# search packages used by KDE 
+# search packages used by KDE
 if(WIN32)
   find_package(KDEWIN32 REQUIRED)
   # detect oxygen icon dir at configure time based on KDEDIRS - there may be different package installation locations
diff --git a/data/htmlview/CMakeLists.txt b/data/htmlview/CMakeLists.txt
--- a/data/htmlview/CMakeLists.txt
+++ b/data/htmlview/CMakeLists.txt
@@ -1,9 +1,8 @@
 FILE(GLOB HTMLVIEW_ICONS "*.png")
 
-install( FILES 
+install( FILES
    ${HTMLVIEW_ICONS}
-   icons.svg 
-   style.css 
+   icons.svg
    DESTINATION  ${DATA_INSTALL_DIR}/kalzium/data/htmlview )
 
 
diff --git a/data/htmlview/characteristics.png b/data/htmlview/characteristics.png
deleted file mode 100644
index db7afa34f0cf5836192943b48e44e451734166be..0000000000000000000000000000000000000000
GIT binary patch
literal 0
Hc$@<O00001

literal 222
zc%17D@N?(olHy`uVBq!ia0y~yU{nIKnK^(2gHTYcFObqMag8W(E=o--$;{7F2+7P%
zW$?{cFfvx~P0Um<GB7YzFf_L^1tJp#Z39CCgXLUDoPpZdOFVsD*{`yS^IM7RSL+G}
z3UL;AL>4nJ@ErzW#^d=bQh<Ui>5jgR3=A9lx&I`x0{Ld1E{-7@=aXxWFtGI`e6m+I
z;%D3N>A;nGHn)<4|1-P_Bzn^>*0-oO_Z&QN;D`YiN5e%0B@Tv%)oiQ>7>wS69Pa7r
K=d#Wzp$P!1DLr!l

diff --git a/data/htmlview/header.png b/data/htmlview/header.png
deleted file mode 100644
index 56eb9596d50f488cd7d1d513528187a90a8dbe96..0000000000000000000000000000000000000000
GIT binary patch
literal 0
Hc$@<O00001

literal 256
zc%17D@N?(olHy`uVBq!ia0vp^dO$40!2~2HW=b6cQrac15hcz=sfi_-`FRQ<nYpP9
zzWEA9#tOcPnF>Y*2Br#z=2oUARtClj+6IOO1_!JBR{^!Lmw5WRvR`Et7ci3kVD+;d
zD8yOd5n0T@z;_sg8IR|$NC676q&xaLGB9lH=l+w(3gkz4x;TbZ+<H50qacF<57WV7
zX7>_%cN4w^t*S@Uo9sDM<cc+ucX?ZCuzHzv-JB}z`sNh#(uJqET~8Ti99KDU)Y8Xq
vg3J03DmCA^R;h^Z&lXNQ^e25n&@+b8liF=j*4Iseb})Fl`njxgN@xNA7*$O{

diff --git a/data/htmlview/style.css b/data/htmlview/style.css
deleted file mode 100644
--- a/data/htmlview/style.css
+++ /dev/null
@@ -1,93 +0,0 @@
-body
-{
-	font-family:'arial';
-}
-
-/* The outer div */
-div.chemdata
-{
-	border: 1px solid rgb(50,80,150);
-	overflow:visible;
-}
-
-/* The header div */
-div.chemdata div
-{
-	background-image:url('header.png');
-}
-
-/* The table inside the header div */
-div.chemdata div table
-{
-	margin:0px;
-	width:100%;
-	color:rgb(240,240,240);
-	font-weight:bold;
-}
-
-/* The td inside the header table */
-div.chemdata div table td
-{
-	padding-left:4px;
-}
-
-/* The second td inside the header table */
-div.chemdata div table td+td
-{
-	font-size:80%;
-}
-
-/* The third td inside the header table */
-div.chemdata div table td+td+td
-{
-	text-align:right;
-	font-size:80%;
-}
-
-table.header
-{
-  	table-layout:fixed;
-}
-
-/* The link color inside the header table */
-table.header a
-{
-        color: rgb(240,240,240);
-}
-
-/* The table containing the characterstics */
-table.characterstics
-{
-	background-color: white;
-	background-image:url('characteristics.png');
-	background-repeat:repeat-y;
-	width:100%;
-}
-
-/* The td's inside the characterstics-table */
-table.characterstics td
-{
-	padding:3px;
-	padding-left:5px;
-	vertical-align:middle;
-	text-align:center;
-}
-
-/* The second td inside the characterstics-table (text) */
-table.characterstics td+td
-{
-	text-align:left;
-}
-
-table.isotopes td
-{
-	border-left:1px #000000 solid;
-	border-bottom:1px #000000 solid;
-}
-
-table.isotopes
-{
-	border-right:1px #000000 solid;
-	border-top:1px #000000 solid;
-}
-
diff --git a/libscience/isotopeparser.h b/libscience/isotopeparser.h
--- a/libscience/isotopeparser.h
+++ b/libscience/isotopeparser.h
@@ -33,7 +33,7 @@
      * Constructor
      */
     IsotopeParser();
-    ~IsotopeParser();
+    ~IsotopeParser() override;
     bool startElement(const QString &, const QString &localName, const QString &,
                       const QXmlAttributes &attrs) override;
 
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -138,10 +138,15 @@
 add_executable(kalzium ${kalzium_SRCS})
 
 target_link_libraries(kalzium
+    KF5::Completion
+    KF5::ConfigWidgets
+    KF5::ItemViews
+    KF5::KIOWidgets
     KF5::Plotting
-    KF5::KHtml
+    KF5::Service
+    KF5::TextWidgets
     KF5::UnitConversion
-    KF5::ItemViews
+    KF5::XmlGui
     Qt5::Script
     Qt5::Svg
     science
diff --git a/src/detailinfodlg.h b/src/detailinfodlg.h
--- a/src/detailinfodlg.h
+++ b/src/detailinfodlg.h
@@ -26,9 +26,10 @@
 class OrbitsWidget;
 class SpectrumViewImpl;
 
+class KActionCollection;
 class QLabel;
 class QStackedWidget;
-class KActionCollection;
+class QTextBrowser;
 class KHTMLPart;
 
 /**
@@ -77,7 +78,7 @@
     DetailedGraphicalOverview *dTab;
 //X         QLabel *piclabel;
     OrbitsWidget *wOrbits;
-    QMap<QString, KHTMLPart*> m_htmlpages;
+    QMap<QString, QTextBrowser*> m_htmlpages;
 
     int m_tableTyp;
 
@@ -104,14 +105,14 @@
      * @returns the pointer to the resulting KHTMLPart, needed for
      * writing HTML code on it
      */
-    KHTMLPart* addHTMLTab(const QString& title, const QString& icontext, const QString& iconname);
+    QTextBrowser* addHTMLTab(const QString& title, const QString& icontext, const QString& iconname);
     /**
      * Change the HTML code in an HTML page.
      *
-     * @param htmlpart the KHTMLPart to edit
+     * @param browser the QTextBrowser to edit
      * @param htmlcode the HTML code to display
      */
-    void fillHTMLTab(KHTMLPart* htmlpart, const QString& htmlcode);
+    void fillHTMLTab(QTextBrowser *browser, const QString& htmlcode);
 
     /**
      * Creates a localized link to Wikipedia.
diff --git a/src/detailinfodlg.cpp b/src/detailinfodlg.cpp
--- a/src/detailinfodlg.cpp
+++ b/src/detailinfodlg.cpp
@@ -35,14 +35,11 @@
 #include <QLocale>
 #include <QStackedWidget>
 #include <QStandardPaths>
+#include <QTextBrowser>
 #include <QUrl>
 
-#include <dom/html_base.h>
-#include <dom/html_document.h>
 #include <KActionCollection>
 #include <KConfig>
-#include <KHTMLPart>
-#include <KHTMLView>
 #include <KHelpClient>
 #include <KPageDialog>
 #include <KPageWidgetModel>
@@ -130,58 +127,31 @@
     m_tableTyp = tableTyp;
 }
 
-KHTMLPart* DetailedInfoDlg::addHTMLTab(const QString& title, const QString& icontext, const QString& iconname)
+QTextBrowser* DetailedInfoDlg::addHTMLTab(const QString& title, const QString& icontext, const QString& iconname)
 {
     QWidget* frame = new QWidget(this);
     KPageWidgetItem *item = addPage(frame, title);
     item->setHeader(icontext);
     item->setIcon(QIcon::fromTheme(iconname));
     QVBoxLayout *layout = new QVBoxLayout(frame);
     layout->setContentsMargins(0, 0, 0, 0);
-
-    KHTMLPart *w = new KHTMLPart(frame, frame);
-    w->setJScriptEnabled(false);
-    w->setJavaEnabled(false);
-    w->setMetaRefreshEnabled(false);
-    w->setPluginsEnabled(false);
-    connect(w->browserExtension(), &KParts::BrowserExtension::openUrlRequest, this, &DetailedInfoDlg::slotLinkClicked);
-    layout->addWidget(w->view());
-
-    return w;
+    QTextBrowser *browser = new QTextBrowser(frame);
+    browser->setOpenExternalLinks(true);
+    layout->addWidget(browser);
+    return browser;
 }
 
-void DetailedInfoDlg::fillHTMLTab(KHTMLPart* htmlpart, const QString& htmlcode)
+void DetailedInfoDlg::fillHTMLTab(QTextBrowser *browser, const QString& htmlcode)
 {
-    if (!htmlpart) {
+    if (!browser) {
         return;
     }
-
-    htmlpart->begin();
-    htmlpart->write(htmlcode);
-
-    // set the background color of the document to match that of the dialog
-    DOM::HTMLElement element = htmlpart->htmlDocument().body();
-    if (element.tagName() == "body") {
-        const QColor backgroundColor = palette().window().color();
-        ((DOM::HTMLBodyElement)element).setBgColor(backgroundColor.name());
-    }
-
-    htmlpart->end();
+    browser->setHtml(htmlcode);
 }
 
 QString DetailedInfoDlg::getHtml(DATATYPE type)
 {
-    QString html =
-        "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\" \"http://www.w3.org/TR/html4/loose.dtd\">"
-        "<html><head><title>Chemical data</title>"
-        "<link rel=\"stylesheet\" type=\"text/css\" href=\"file://" + m_baseHtml + "style.css\" />"
-        "<base href=\"" + m_baseHtml + "\"/></head><body>"
-        "<div class=\"chemdata\"><div><table summary=\"header\" class=\"header\">"
-        "<tr><td>" + m_element->dataAsString(ChemicalDataObject::symbol) + "</td><td>"
-        + createWikiLink(m_element->dataAsString(ChemicalDataObject::name)) + "</td><td>"
-        + i18n("Block: %1", m_element->dataAsString(ChemicalDataObject::periodTableBlock)) +
-        "</td></tr></table></div>"
-        "<table summary=\"characteristics\" class=\"characterstics\">";
+    QString html = "<table width=\"100%\" summary=\"characteristics\">";
 
     switch (type) {
     case MISC:
@@ -305,7 +275,7 @@
 
         //http://education.jlab.org/itselemental/ele001.html
         html.append ("<tr><td>");
-        html.append ("<a href=\"http://");        // http://
+        html.append ("<a href=\"https://");        // https://
         html.append ("education.jlab.org/itselemental/ele");
         html.append (QStringLiteral("%1").arg(m_element->dataAsString(ChemicalDataObject::atomicNumber), 3, '0'));
         html.append (".html");
@@ -316,7 +286,7 @@
 
         // FIXME only works with english locals
         html.append ("<tr><td>");
-        html.append ("<a href=\"http://");        // http://
+        html.append ("<a href=\"https://");        // https://
         html.append ("www.webelements.com/");
         if (QLocale().uiLanguages().first().startsWith(QLatin1String("en"))) {
             html.append (m_element->dataAsString(ChemicalDataObject::name).toLower()); // hydrogen
@@ -346,24 +316,21 @@
     QList<Isotope*> list = KalziumDataObject::instance()->isotopes(m_elementNumber);
 
     QString html;
-
-    html = QStringLiteral("<table class=\"isotopes\" cellspacing=\"0\"><tr><td colspan=\"7\">");
-    html += i18n("Isotope-Table");
-    html += QLatin1String("</tr></td><tr><td><b>");
+    html = QStringLiteral("<table cellspacing=\"0\" border=\"1\" cellpadding=\"3\" style=\"border-style: solid;\"><tr><th>");
     html += i18n("Mass");
-    html += QLatin1String("</b></td><td><b>");
+    html += QLatin1String("</th><th>");
     html += i18n("Neutrons");
-    html += QLatin1String("</b></td><td><b>");
+    html += QLatin1String("</th><th>");
     html += i18n("Percentage");
-    html += QLatin1String("</b></td><td><b>");
+    html += QLatin1String("</th><th>");
     html += i18n("Half-life period");
-    html += QLatin1String("</b></td><td><b>");
+    html += QLatin1String("</th><th>");
     html += i18n("Energy and Mode of Decay");
-    html += QLatin1String("</b></td><td><b>");
+    html += QLatin1String("</th><th>");
     html += i18n("Spin and Parity");
-    html += QLatin1String("</b></td><td><b>");
+    html += QLatin1String("</th><th>");
     html += i18n("Magnetic Moment");
-    html += QLatin1String("</b></td></tr>");
+    html += QLatin1String("</th></tr>");
 
     foreach (Isotope *isotope, list) {
         html.append("<tr><td align=\"right\">");
@@ -378,7 +345,8 @@
         }
         html.append("</td><td>");
         if ((isotope)->halflife() > 0.0) {
-            html.append(i18nc("The first argument is the value, the second is the unit. For example '17 s' for '17 seconds',.", "%1 %2", (isotope)->halflife(), (isotope)->halflifeUnit()));
+            html.append(i18nc("The first argument is the value, the second is the unit. For example '17 s' for '17 seconds',.", "%1 %2",
+                              (isotope)->halflife(), (isotope)->halflifeUnit()));
         }
         html.append("</td><td>");
         if ((isotope)->alphalikeliness() > 0.0) {
@@ -490,7 +458,6 @@
     m_htmlpages[QStringLiteral("isotopes")] = addHTMLTab(i18n("Isotopes"), i18n("Isotopes"), QStringLiteral("isotopemap"));
     m_htmlpages[QStringLiteral("misc")] = addHTMLTab(i18n("Miscellaneous"), i18n("Miscellaneous"), QStringLiteral("misc"));
 
-
     // spectrum widget tab
     QWidget *m_pSpectrumTab = new QWidget(this);
     item = addPage(m_pSpectrumTab, i18n("Spectrum"));
@@ -514,13 +481,12 @@
 {
     // reading the most common data
     const QString element_name = m_element->dataAsString(ChemicalDataObject::name);
-//     const QString element_symbol = m_element->dataAsString(ChemicalDataObject::symbol);
+    const QString element_symbol = m_element->dataAsString(ChemicalDataObject::symbol);
+    const QString element_block = m_element->dataAsString(ChemicalDataObject::periodTableBlock);
 
     // updating caption
-    setWindowTitle(i18nc("For example Carbon (6)", "%1 (%2)", element_name, m_elementNumber));
-
-    // updating overview tab
-//     dTab->setElement(m_elementNumber);
+    setWindowTitle(i18nc("For example: [C] Carbon (6 - Block p)", "[%1] %2 (%3 - Block %4)",
+                         element_symbol, element_name, m_elementNumber, element_block));
 
     //X      // updating picture tab
     //X      QString picpath = m_picsdir + element_symbol + ".jpg";
@@ -573,16 +539,16 @@
     QString language(QLocale().uiLanguages().first());
 
     //Wikipedia.org
-    html.append ("<a href=\"http://");         // http://
+    html.append ("<a href=\"https://");         // https://
     html.append (language.split('-').at(0));   // en.
     html.append (".wikipedia.org/wiki/");      // wikipedia.org
     html.append (link);                        // /hydrogen
     html.append ("\" target=\"_blank\" > ");
     html.append (displayString);
     html.append ("</a>");
-    // Example from the comment "http://en.wikipedia.org/wiki/hydrogen"
+    // Example from the comment "https://en.wikipedia.org/wiki/hydrogen"
 
-     return html;
+    return html;
 }
 
 void DetailedInfoDlg::slotLinkClicked(const QUrl &url)
diff --git a/src/kalzium.cpp b/src/kalzium.cpp
--- a/src/kalzium.cpp
+++ b/src/kalzium.cpp
@@ -61,7 +61,6 @@
 #include <KActionCollection>
 #include <KConfigDialog>
 #include <KLocalizedString>
-#include <KParts/Part>
 #include <KPluginLoader>
 #include <KSelectAction>
 #include <KServiceTypeTrader>
diff --git a/src/kdeeduglossary.h b/src/kdeeduglossary.h
--- a/src/kdeeduglossary.h
+++ b/src/kdeeduglossary.h
@@ -234,8 +234,6 @@
     Private * const d;
 
     Q_PRIVATE_SLOT(d, void itemActivated(QTreeWidgetItem *, int))
-    Q_PRIVATE_SLOT(d, void displayItem(const QUrl &, const KParts::OpenUrlArguments &,
-                                       const KParts::BrowserArguments &))
 };
 
 #endif // KDEEDUGLOSSARY_H
diff --git a/src/kdeeduglossary.cpp b/src/kdeeduglossary.cpp
--- a/src/kdeeduglossary.cpp
+++ b/src/kdeeduglossary.cpp
@@ -22,8 +22,6 @@
 
 #include <KActionCollection>
 #include <KConfigGroup>
-#include <KHTMLPart>
-#include <KHTMLView>
 #include <KLocalizedString>
 #include <KTreeWidgetSearchLine>
 
@@ -40,6 +38,7 @@
 #include <QRegExp>
 #include <QSplitter>
 #include <QStringList>
+#include <QTextBrowser>
 #include <QTreeWidget>
 #include <QVBoxLayout>
 
@@ -108,15 +107,12 @@
 
         // slots
         void itemActivated(QTreeWidgetItem * item, int column);
-        // The user clicked on a href. Find and display the right item
-        void displayItem(const QUrl &url, const KParts::OpenUrlArguments& arguments,
-                         const KParts::BrowserArguments &browserArguments);
 
         GlossaryDialog *q;
 
         QList< GlossaryInfo > m_glossaries;
 
-        KHTMLPart *m_htmlpart;
+        QTextBrowser *m_htmlpart;
         QTreeWidget *m_glosstree;
         KTreeWidgetSearchLine *m_search;
         QString m_htmlbasestring;
@@ -242,17 +238,17 @@
         reflist.clear();
         GlossaryItem *item = new GlossaryItem();
 
-        itemElement = (const QDomElement&) itemList.item(i).toElement();
+        itemElement = itemList.item(i).toElement();
 
         QDomNode nameNode = itemElement.namedItem(QStringLiteral("name"));
         QDomNode descNode = itemElement.namedItem(QStringLiteral("desc"));
 
         QString picName = itemElement.namedItem(QStringLiteral("picture")).toElement().text();
-        QDomElement refNode = (const QDomElement&) itemElement.namedItem(QStringLiteral("references")).toElement();
+        QDomElement refNode = itemElement.namedItem(QStringLiteral("references")).toElement();
 
         QString desc = i18n(descNode.toElement().text().toUtf8().constData());
         if (!picName.isEmpty()) {
-            desc.prepend("[img]" + picName + "[/img][brclear][br]");
+            desc.prepend("[br][img]" + picName + "[/img][brclear][br]");
         }
 
         item->setName(i18n(nameNode.toElement().text().toUtf8().constData()));
@@ -349,12 +345,27 @@
 
     d->m_search->addTreeWidget(d->m_glosstree);
 
-    d->m_htmlpart = new KHTMLPart(vs);
+    d->m_htmlpart = new QTextBrowser(vs);
+    d->m_htmlpart->setOpenLinks(false);
 
-    connect(d->m_htmlpart->browserExtension(), SIGNAL(openUrlRequestDelayed(QUrl,KParts::OpenUrlArguments,KParts::BrowserArguments)),
-            this, SLOT(displayItem(QUrl,KParts::OpenUrlArguments,KParts::BrowserArguments)));
     connect(d->m_glosstree, SIGNAL(itemActivated(QTreeWidgetItem*,int)),
             this, SLOT(itemActivated(QTreeWidgetItem*,int)));
+    connect(d->m_htmlpart, &QTextBrowser::anchorClicked, this, [=](const QUrl &link){
+        // using the "path" part of a qurl as reference
+        QString myurl = link.path().toLower();
+        QTreeWidgetItemIterator it(this->d->m_glosstree);
+        while (*it) {
+            if ((*it)->type() == GlossaryTreeItemType && (*it)->text(0).toLower() == myurl) {
+                 // force the item to be selected
+                 this->d->m_glosstree->setCurrentItem(*it);
+                 // display its content
+                 emit this->d->itemActivated((*it), 0);
+                 break;
+            } else {
+                ++it;
+            }
+         }
+    });
 
     QDialogButtonBox *buttonBox = new QDialogButtonBox(QDialogButtonBox::Close);
     connect(buttonBox, &QDialogButtonBox::rejected, this, &GlossaryDialog::reject);
@@ -377,25 +388,6 @@
     QDialog::keyPressEvent(e);
 }
 
-void GlossaryDialog::Private::displayItem(const QUrl &url, const KParts::OpenUrlArguments &, const KParts::BrowserArguments &)
-{
-    // using the "path" part of a qurl as reference
-    QString myurl = url.path().toLower();
-
-    QTreeWidgetItemIterator it(m_glosstree);
-    while (*it) {
-        if ((*it)->type() == GlossaryTreeItemType && (*it)->text(0).toLower() == myurl) {
-             // force the item to be selected
-             m_glosstree->setCurrentItem(*it);
-             // display its content
-             itemActivated((*it), 0);
-             break;
-        } else {
-            ++it;
-        }
-     }
-}
-
 void GlossaryDialog::Private::rebuildTree()
 {
     m_glosstree->clear();
@@ -477,9 +469,7 @@
     html = m_htmlbasestring.arg(html);
     html += glossitem->toHtml() + "</body></html>";
 
-    m_htmlpart->begin();
-    m_htmlpart->write(html);
-    m_htmlpart->end();
+    m_htmlpart->setHtml(html);
 }
 
 void GlossaryItem::setRef(const QStringList& s)