Here is working solution (that romainl mentioned in comment under the answer):
Redirect the output of a Vim or external command into a scratch buffer
Description of this script is in this answer for question:
Can listings in the awful 'more' be displayed, instead, in a vim window?
Described and used scratch buffer is similar to less command. Navigation and search function is available in it.
Checked in Vim with clipboard support:
VIM - Vi IMproved 8.1 (2018 May 18, compiled Dec 07 2023 15:42:49)
Included patches: 1-213, 1840, 214-579, 1969, 580-1848, 4975, 5023, 2110, 1849-1854, 1857, 1855-1857, 1331, 1858, 1858-1859, 1873, 1860-1969, 1992, 1970-1992, 2010, 1993-2068, 2106, 2069-2106, 2108, 2107-2109, 2109-2111, 2111-2112, 2112-2269, 3612, 3625, 3669, 3741, 1847
under Ubuntu 20.04
sudo apt install vim
sudo apt install vim-gtk3
apt - How do I install vim-gnome on Ubuntu 19.10?
Ctrl-d). – VanLaser Dec 05 '15 at 08:30-- More -- SPACE/d/j: screen/page/line down, b/u/k: up, q: quitin the commandline. – the_velour_fog Dec 05 '15 at 08:34:letthen don't hitEnter, butTaborCtrl-d- you'll have a list of existing variables, displayed in "more" style - now hitEsc, write a few letters, hitTaborCtrl-dagain ... and so on until you find the variable you want. Actually, to see the value of a variable, perhaps you should useechoinstead? (Orset variable-name?for options) – VanLaser Dec 05 '15 at 08:43Ctrl-dand the echo trick worked nicely, thanks! – the_velour_fog Dec 05 '15 at 09:03