you can use the zenity to displays the query output as html table.
first implement bash script with following code:
cat > '/tmp/sql.op'; zenity --text-info --html --filename='/tmp/sql.op';
save it like mypager.sh
Then export the environment variable PAGER by set full path of the script as value.
for example:- export PAGER='/path/mypager.sh'
Then login to the psql program then execute the command \H
And finally execute any query,the tabled output will displayed in the zenity in html table format.