Use doas(1) so that normal users can use sshfs(1).

On OpenBSD sshfs(1) does not seem to support the "-o password_stdin" option.
Workaround suggested in FreeBSD:
https://svnweb.freebsd.org/ports/head/deskutils/kdeconnect-kde/files/patch-plugins_sftp_mounter.cpp?view=markup

Cope with diffie-hellman-group14-sha1 removal in OpenSSH 8.2:
https://git.archlinux.org/svntogit/packages.git/plain/trunk/kdeconnect-openssh-8.2.patch?h=packages/kdeconnect

Index: plugins/sftp/mounter.cpp
--- plugins/sftp/mounter.cpp.orig
+++ plugins/sftp/mounter.cpp
@@ -96,7 +96,7 @@ void Mounter::onPackageReceived(const NetworkPacket &n
 
     QDir().mkpath(m_mountPoint);
 
-    const QString program = QStringLiteral("sshfs");
+    const QString program = QStringLiteral("/usr/bin/doas");
 
     QString path;
     if (np.has(QStringLiteral("multiPaths")))
@@ -116,7 +116,7 @@ void Mounter::onPackageReceived(const NetworkPacket &n
     }
 
     const QStringList arguments =
-        QStringList() << QStringLiteral("%1@%2:%3")
+        QStringList() << QStringLiteral("${LOCALBASE}/bin/sshfs") << QStringLiteral("%1@%2:%3")
                              .arg(np.get<QString>(QStringLiteral("user")),
                                   ip,
                                   path)
@@ -130,7 +130,9 @@ void Mounter::onPackageReceived(const NetworkPacket &n
                       << QStringLiteral("-o") << QStringLiteral("PubkeyAcceptedKeyTypes=+ssh-rsa") // https://bugs.kde.org/show_bug.cgi?id=443155
                       << QStringLiteral("-o") << QStringLiteral("uid=") + QString::number(getuid()) << QStringLiteral("-o")
                       << QStringLiteral("gid=") + QString::number(getgid()) << QStringLiteral("-o") << QStringLiteral("reconnect") << QStringLiteral("-o")
-                      << QStringLiteral("ServerAliveInterval=30") << QStringLiteral("-o") << QStringLiteral("password_stdin");
+                      << QStringLiteral("ServerAliveInterval=30") << QStringLiteral("-o") << QStringLiteral("-o") << QStringLiteral("KexAlgorithms=+diffie-hellman-group14-sha1")
+                      << QStringLiteral("-o") << QStringLiteral("allow_other") << QStringLiteral("-o") << QStringLiteral("umask=0022")
+                      << QStringLiteral("-o") << QStringLiteral("ssh_command=${LOCALBASE}/bin/sshpass -p %1 %2").arg(np.get<QString>(QStringLiteral("password")), QStringLiteral("/usr/bin/ssh"));
 
     m_proc->setProgram(program, arguments);
 
@@ -138,8 +140,8 @@ void Mounter::onPackageReceived(const NetworkPacket &n
     m_proc->start();
 
     // qCDebug(KDECONNECT_PLUGIN_SFTP) << "Passing password: " << np.get<QString>("password").toLatin1();
-    m_proc->write(np.get<QString>(QStringLiteral("password")).toLatin1());
-    m_proc->write("\n");
+    //m_proc->write(np.get<QString>(QStringLiteral("password")).toLatin1());
+    //m_proc->write("\n");
 }
 
 void Mounter::onStarted()