diff --git a/src/IO/http.cc b/src/IO/http.cc
index 5652fd1..f0d4acc 100644
--- a/src/IO/http.cc
+++ b/src/IO/http.cc
@@ -127,13 +127,13 @@ int a_Http_init(void)
    char *env_proxy = getenv("http_proxy");
 
    HTTP_Language_hdr = prefs.http_language ?
-      dStrconcat("Accept-Language: ", prefs.http_language, "\r\n", NULL) :
+      dStrconcat("Accept-Language: ", prefs.http_language.value().c_str(), "\r\n", NULL) :
       dStrdup("");
 
    if (env_proxy && strlen(env_proxy))
       HTTP_Proxy = a_Url_new(env_proxy, NULL).release();
    if (!HTTP_Proxy && prefs.http_proxy)
-      HTTP_Proxy = a_Url_dup(prefs.http_proxy).release();
+      HTTP_Proxy = a_Url_dup(prefs.http_proxy.get()).release();
 
 /*  This allows for storing the proxy password in "user:passwd" format
  * in dillorc, but as this constitutes a security problem, it was disabled.
@@ -159,7 +159,7 @@ int a_Http_proxy_auth(void)
  */
 void a_Http_set_proxy_passwd(const char *str)
 {
-   char *http_proxyauth = dStrconcat(prefs.http_proxyuser, ":", str, NULL);
+   char *http_proxyauth = dStrconcat(prefs.http_proxyuser.value().c_str(), ":", str, NULL);
    HTTP_Proxy_Auth_base64 = a_Misc_encode_base64(http_proxyauth);
    dFree(http_proxyauth);
 }
@@ -337,10 +337,10 @@ static char *Http_get_referer(const DilloUrl *url)
 {
    char *referer = NULL;
 
-   if (!strcmp(prefs.http_referer, "host")) {
+   if (!strcmp(prefs.http_referer.c_str(), "host")) {
       referer = dStrconcat("Referer: ", URL_SCHEME(url), "://",
                            URL_AUTHORITY(url), "/", "\r\n", NULL);
-   } else if (!strcmp(prefs.http_referer, "path")) {
+   } else if (!strcmp(prefs.http_referer.c_str(), "path")) {
       referer = dStrconcat("Referer: ", URL_SCHEME(url), "://",
                            URL_AUTHORITY(url),
                            URL_PATH_(url) ? URL_PATH(url) : "/", "\r\n", NULL);
@@ -684,7 +684,7 @@ static int Http_must_use_proxy(const char *hostname)
       if (prefs.no_proxy) {
          size_t host_len = strlen(hostname);
 
-         np = dStrdup(prefs.no_proxy);
+         np = dStrdup(prefs.no_proxy.value().c_str());
          for (p = np; (tok = dStrsep(&p, " "));  ) {
             int start = host_len - strlen(tok);
 
diff --git a/src/IO/tls_openssl.cc b/src/IO/tls_openssl.cc
index e297dbc..e1eea32 100644
--- a/src/IO/tls_openssl.cc
+++ b/src/IO/tls_openssl.cc
@@ -58,6 +58,8 @@
 #include <openssl/x509v3.h>    /* for hostname checking */
 #include <openssl/crypto.h>    /* OpenSSL_version */
 
+#include <sstream>
+
 #define CERT_STATUS_NONE 0
 #define CERT_STATUS_RECEIVING 1
 #define CERT_STATUS_CLEAN 2
@@ -324,26 +326,28 @@ void a_Tls_openssl_init(void)
  */
 static int Tls_save_certificate_home(X509 * cert)
 {
-   char buf[4096];
+   std::string buf;
 
    FILE * fp = NULL;
    uint_t i = 0;
    int ret = 1;
 
    /* Attempt to create .flenser/certs blindly - check later */
-   snprintf(buf, 4096, "%s/.flenser/", dGethomedir());
-   mkdir(buf, 01777);
-   snprintf(buf, 4096, "%s/.flenser/certs/", dGethomedir());
-   mkdir(buf, 01777);
+   buf= dGethomedir_string().value() + "/.flenser/";
+   mkdir(buf.c_str(), 01777);
+   buf= dGethomedir_string().value() + "/.flenser/certs/";
+   mkdir(buf.c_str(), 01777);
 
    do {
-      snprintf(buf, 4096, "%s/.flenser/certs/%lx.%u",
-               dGethomedir(), X509_subject_name_hash(cert), i);
+      std::ostringstream oss;
+      oss << dGethomedir_string().value() + "/.flenser/certs/" << X509_subject_name_hash( cert ) << '.' << i;
+      buf= oss.str();
+      
 
-      fp=fopen(buf, "r");
+      fp=fopen(buf.c_str(), "r");
       if (fp == NULL){
          /* File name doesn't exist so we can use it safely */
-         fp=fopen(buf, "w");
+         fp=fopen(buf.c_str(), "w");
          if (fp == NULL){
             MSG("Unable to open cert save file in home dir\n");
             break;
diff --git a/src/dicache.cc b/src/dicache.cc
index 4c9ae9c..2c82091 100644
--- a/src/dicache.cc
+++ b/src/dicache.cc
@@ -80,7 +80,7 @@ void a_Dicache_init(void)
 
    if (prefs.ignore_image_formats) {
       for (int i = 0; i < DIC_MAX; i++) {
-         if (dStriAsciiStr(prefs.ignore_image_formats, format_name[i])) {
+         if (dStriAsciiStr(prefs.ignore_image_formats.value().c_str(), format_name[i])) {
             disabled_formats[i] = 1;
             _MSG("Image format %s disabled\n", format_name[i]);
          }
diff --git a/src/flenser.cc b/src/flenser.cc
index eb36d83..96a79cb 100644
--- a/src/flenser.cc
+++ b/src/flenser.cc
@@ -407,7 +407,7 @@ int main(int argc, char **argv)
    // Sets WM_CLASS hint on X11
    Fl_Window::default_xclass("flenser");
 
-   Fl::scheme(prefs.theme);
+   Fl::scheme(prefs.theme.c_str());
 
    // Disable drag and drop as it crashes on MacOSX
    Fl::dnd_text_ops(0);
@@ -445,7 +445,7 @@ int main(int argc, char **argv)
 
    /* Proxy authentication */
    if (prefs.http_proxyuser && !a_Http_proxy_auth()) {
-      const char *passwd = a_UIcmd_get_passwd(prefs.http_proxyuser);
+      const char *passwd = a_UIcmd_get_passwd(prefs.http_proxyuser.value().c_str());
       if (passwd) {
          a_Http_set_proxy_passwd(passwd);
       } else {
@@ -462,8 +462,8 @@ int main(int argc, char **argv)
           strcmp(URL_PATH(prefs.start_page), "blank") == 0)
          a_UIcmd_open_url(bw, NULL); // NULL URL focuses location
       else {
-         a_UIcmd_open_url(bw, prefs.start_page);
-         a_UIcmd_set_location_text(bw, URL_STR(prefs.start_page));
+         a_UIcmd_open_url(bw, prefs.start_page.get());
+         a_UIcmd_set_location_text(bw, URL_STR(prefs.start_page.get()));
       }
    } else {
       for (int i = idx; i < argc; i++) {
diff --git a/src/nav.cc b/src/nav.cc
index 5307f85..86e3f40 100644
--- a/src/nav.cc
+++ b/src/nav.cc
@@ -448,7 +448,7 @@ void a_Nav_forw(BrowserWindow *bw)
  */
 void a_Nav_home(BrowserWindow *bw)
 {
-   a_Nav_push(bw, prefs.home, NULL);
+   a_Nav_push(bw, prefs.home.get(), NULL);
 }
 
 /*
diff --git a/src/prefs.cc b/src/prefs.cc
index 7fa62cb..1897810 100644
--- a/src/prefs.cc
+++ b/src/prefs.cc
@@ -62,21 +62,17 @@ void a_Prefs_init(void)
    prefs.xpos = PREFS_GEOMETRY_DEFAULT_XPOS;
    prefs.ypos = PREFS_GEOMETRY_DEFAULT_YPOS;
 
-   prefs.home = a_Url_new(PREFS_HOME, NULL).release();
-   prefs.http_language = NULL;
-   prefs.http_proxy = NULL;
+   prefs.home = a_Url_new(PREFS_HOME, NULL);
    prefs.http_max_conns = 6;
    prefs.http_persistent_conns = TRUE;
-   prefs.http_proxyuser = NULL;
-   prefs.http_referer = dStrdup(PREFS_HTTP_REFERER);
+   prefs.http_referer = PREFS_HTTP_REFERER;
    prefs.http_strict_transport_security = TRUE;
    prefs.http_force_https = FALSE;
-   prefs.http_user_agent = dStrdup(PREFS_HTTP_USER_AGENT);
+   prefs.http_user_agent = PREFS_HTTP_USER_AGENT;
    prefs.limit_text_width = FALSE;
    prefs.adjust_min_width = TRUE;
    prefs.adjust_table_min_width = TRUE;
    prefs.load_images=TRUE;
-   prefs.ignore_image_formats = NULL;
    prefs.load_background_images=FALSE;
    prefs.load_stylesheets=TRUE;
    prefs.middle_click_drags_page = TRUE;
@@ -84,11 +80,11 @@ void a_Prefs_init(void)
    prefs.right_click_closes_tab = TRUE;
    prefs.scroll_switches_tabs = TRUE;
    prefs.scroll_switches_tabs_reverse = FALSE;
-   prefs.no_proxy = dStrdup(PREFS_NO_PROXY);
+   prefs.no_proxy = PREFS_NO_PROXY;
    prefs.link_actions = dList_new(16);
    prefs.panel_size = P_medium;
    prefs.parse_embedded_css=TRUE;
-   prefs.save_dir = dStrdup(PREFS_SAVE_DIR);
+   prefs.save_dir = PREFS_SAVE_DIR;
    prefs.scroll_step = 100;
    prefs.scroll_page_overlap = 50;
    prefs.search_urls = dList_new(16);
@@ -116,9 +112,9 @@ void a_Prefs_init(void)
    prefs.show_tooltip = TRUE;
    prefs.show_ui_tooltip = TRUE;
    prefs.small_icons = FALSE;
-   prefs.start_page = a_Url_new(PREFS_START_PAGE, NULL).release();
-   prefs.new_tab_page = a_Url_new(PREFS_NEW_TAB_PAGE, NULL).release();
-   prefs.theme = dStrdup(PREFS_THEME);
+   prefs.start_page = a_Url_new(PREFS_START_PAGE, NULL);
+   prefs.new_tab_page = a_Url_new(PREFS_NEW_TAB_PAGE, NULL);
+   prefs.theme = PREFS_THEME;
    prefs.ui_button_highlight_color = -1;
    prefs.ui_fg_color = -1;
    prefs.ui_main_bg_color = -1;
@@ -142,22 +138,11 @@ void a_Prefs_init(void)
  *  memory-deallocation.
  *  (Call this one at exit time)
  */
-void a_Prefs_freeall(void)
+void a_Prefs_freeall()
 {
    int i;
 
-   delete prefs.home;
-   dFree(prefs.http_language);
-   delete prefs.http_proxy;
-   dFree(prefs.http_proxyuser);
-   dFree(prefs.http_referer);
-   dFree(prefs.http_user_agent);
-   dFree(prefs.no_proxy);
-   dFree(prefs.save_dir);
    for (i = 0; i < dList_length(prefs.search_urls); ++i)
       dFree(dList_nth_data(prefs.search_urls, i));
    dList_free(prefs.search_urls);
-   delete prefs.start_page;
-   delete prefs.new_tab_page;
-   dFree(prefs.theme);
 }
diff --git a/src/prefs.hh b/src/prefs.hh
index ccd9a55..6030c72 100644
--- a/src/prefs.hh
+++ b/src/prefs.hh
@@ -42,16 +42,16 @@ struct DilloPrefs
    int height;
    int xpos;
    int ypos;
-   char *http_language;
+   std::optional< std::string > http_language;
    int32_t http_max_conns;
-   DilloUrl *http_proxy;
-   char *http_proxyuser;
-   char *http_referer;
-   char *http_user_agent;
-   char *no_proxy;
-   DilloUrl *start_page;
-   DilloUrl *home;
-   DilloUrl *new_tab_page;
+   std::unique_ptr< DilloUrl > http_proxy;
+   std::optional< std::string > http_proxyuser;
+   std::string http_referer;
+   std::string http_user_agent;
+   std::optional< std::string > no_proxy;
+   std::unique_ptr< DilloUrl > start_page;
+   std::unique_ptr< DilloUrl > home;
+   std::unique_ptr< DilloUrl > new_tab_page;
    bool allow_white_bg;
    int32_t white_bg_replacement;
    int32_t bg_color;
@@ -68,7 +68,7 @@ struct DilloPrefs
    bool contrast_visited_color;
    bool show_tooltip;
    bool show_ui_tooltip;
-   char *theme;
+   std::string theme;
    int panel_size;
    bool small_icons;
    bool limit_text_width;
@@ -100,7 +100,7 @@ struct DilloPrefs
    bool show_quit_dialog;
    bool fullwindow_start;
    bool load_images;
-   char *ignore_image_formats;
+   std::optional< std::string > ignore_image_formats;
    bool load_background_images;
    bool load_stylesheets;
    bool parse_embedded_css;
@@ -120,7 +120,7 @@ struct DilloPrefs
    bool scroll_switches_tabs_reverse;
    bool search_url_idx;
    Dlist *search_urls;
-   char *save_dir;
+   std::optional< std::string > save_dir;
    bool show_msg;
    bool show_extra_warnings;
    bool middle_click_drags_page;
diff --git a/src/uicmd.cc b/src/uicmd.cc
index 8c2f845..4c35217 100644
--- a/src/uicmd.cc
+++ b/src/uicmd.cc
@@ -810,8 +810,8 @@ void a_UIcmd::a_UIcmd_open_url(BrowserWindow *bw, const DilloUrl *url)
 static void UIcmd_open_url_nbw(BrowserWindow *new_bw, const DilloUrl *url)
 {
    if (!url && prefs.new_tab_page) {
-      if (strcmp(URL_STR(prefs.new_tab_page), "about:blank") != 0)
-         url = prefs.new_tab_page;
+      if (strcmp(URL_STR(prefs.new_tab_page.get()), "about:blank") != 0)
+         url = prefs.new_tab_page.get();
    }
 
    /* When opening a new BrowserWindow (tab or real window) we focus
@@ -892,7 +892,7 @@ void a_UIcmd::a_UIcmd_forw_popup(void *vbw, int x, int y)
  */
 void a_UIcmd::a_UIcmd_home(void *vbw)
 {
-   a_UIcmd_open_url((BrowserWindow*)vbw, prefs.home);
+   a_UIcmd_open_url((BrowserWindow*)vbw, prefs.home.get());
 }
 
 /*
@@ -1030,17 +1030,15 @@ static char *UIcmd_make_save_filename(const DilloUrl *url)
 /*
  * Set the default directory for saving files.
  */
-void a_UIcmd::a_UIcmd_init(void)
+void a_UIcmd::a_UIcmd_init()
 {
-   const char *dir = prefs.save_dir;
+	if( not prefs.save_dir.has_value() ) return;
 
-   if (dir && *dir) {
-      // assert a trailing '/'
-      save_dir =
-         (dir[strlen(dir)-1] == '/')
-         ? dStrdup(dir)
-         : dStrconcat(dir, "/", NULL);
-   }
+    std::string dir= prefs.save_dir.value();
+	// assert a trailing '/'
+	if( dir.back() != '/' ) dir+= '/';
+
+	save_dir = dStrdup( dir.c_str() );
 }
 
 /*