If you use 2 desktops in KDE, you can use different default browsers in these desktops. I like having Firefox as default browser for Personal desktop and Google Chrome for Work.

Let's put it into $HOME/scripts/smart-browser.sh:

smart-browser.sh

#!/usr/bin/env bash
 
# --- Configuration ---
LOG_DIR="$HOME/temp/smartbrowser_logs"
LOGFILE="$LOG_DIR/smartbrowser.log"
# ---------------------
 
# 1. Ensure the log directory exists
mkdir -p "$LOG_DIR"
 
# 2. Check and perform log rotation (clear file if not modified today)
CURRENT_DATE=$(date +'%Y-%m-%d')
 
# Get the last modification date of the log file
if [ -f "$LOGFILE" ]; then
    # Use 'stat' command to get file modification time (platform specific, but common)
    # The format specifier depends on the OS. On Linux (using GNU stat):
    # %y: last modification time
    # %Y: last modification time in seconds since epoch (simpler for comparisons if needed)
    # We'll use the formatted date for simplicity:
    LOG_DATE=$(stat -c '%Y' "$LOGFILE")
    LOG_MOD_DATE=$(date -d "@$LOG_DATE" +'%Y-%m-%d')
else
    # If the file doesn't exist yet, treat its date as 'old' to trigger creation/touch
    LOG_MOD_DATE=""
fi
 
if [[ "$LOG_MOD_DATE" != "$CURRENT_DATE" ]]; then
    # Log file is from a previous day (or doesn't exist). Recreate/truncate it.
    # The 'true > $LOGFILE' command effectively empties the file.
    echo "[INFO] Log file rotated (previous date: $LOG_MOD_DATE)." > "$LOGFILE"
    echo "---" >> "$LOGFILE"
fi
# The file is now either newly created, truncated, or from today.
 
# 3. Get the current desktop number (KDE/KWin specific)
current_desktop=$(qdbus org.kde.KWin /KWin currentDesktop)
 
# 4. Log the script call details
TIMESTAMP=$(date +'%Y-%m-%d %H:%M:%S')
 
printf '[%s] Current desktop: %s, Arguments: %s\n' "$TIMESTAMP" "$current_desktop" "$*" >> "$LOGFILE"
 
# 5. Select and launch the browser based on the desktop number
if [[ "$current_desktop" == "1" ]]; then
    echo "[INFO] Launching Google Chrome..." >> "$LOGFILE"
    google-chrome "$@" >> "$LOGFILE" 2>&1
elif [[ "$current_desktop" == "2" ]]; then
    echo "[INFO] Launching Firefox..." >> "$LOGFILE"
    firefox "$@" >> "$LOGFILE" 2>&1
else
    # Default to Firefox for all other desktops
    echo "[INFO] Launching Firefox (default)..." >> "$LOGFILE"
    firefox "$@" >> "$LOGFILE" 2>&1
fi
 
echo "---" >> "$LOGFILE"
 
exit 0

Use file $HOME/temp/smartbrowser_logs/smartbrowser.log to view logs.

Create a file ~/.local/share/applications/smart-browser.desktop:

[Desktop Entry]
Version=1.0
Name=Smart Browser
Comment=Context-aware browser launcher
Exec=bash -c "$HOME/scripts/smart-browser.sh %u"
Icon=web-browser
Terminal=false
Type=Application
Categories=Network;WebBrowser;
MimeType=text/html;text/xml;application/xhtml+xml;x-scheme-handler/http;x-scheme-handler/https;

xdg-settings set default-web-browser smart-browser.desktop
xdg-mime default smart-browser.desktop x-scheme-handler/http
xdg-mime default smart-browser.desktop x-scheme-handler/https