I was able to work around the issue with this:

RewriteCond %{QUERY_STRING} ^(.*)&(.*)&(.*)$
RewriteRule ^(.*)$ $1?%1&%2&%3 [R,L]

So on the first page load, the bad URL:

image.php?twg_album=&twg_type=png&twg_show=back.png

gets redirected to this good URL:

image.php?twg_album=&twg_type=png&twg_show=back.png

s

I'm seeing additional strangeness on first load versus subsequent loads

First load honors the "Number of thumbnails in a row" setting while subsequent loads ignore this and place as many as will fit

For example with 23 images

First load gives 6 images on first 3 rows and 5 images on last row

Subsequent loads give 14 images on first row and 9 images on second row

Hi,

which browser do you use? Because this is normal url encoding! I tested with chrome and Firefox and both work fine!

See: https://www.tinywebgallery.com/demo/twg_album/03_Mexico+%282004%29

But you are right. at this place no encoding is needed.

I fixed this already in my code:

open bodytag.inc.php and look for

$background_tmp = $install_dir_view . 'image.php?twg_album=' . $album_enc .......

change it to

$background_tmp = $install_dir_view . 'image.php?twg_album=' . $album_enc . '&twg_type=png&twg_show=back.png';

About the

Number of thumbnails in a row

At the first call the gallery does not know the browser width. After 1st call it tries to optimize this because then it is known.

you have "autodetect_maximum_thumbnails" enabled. Therefore this is the expected behavior. If you disable this you get your fixed sizes.

You can also use https://www.tinywebgallery.com/demo/twg_album/01_Administration~01_masonry

then an automatic optimization is done right from the start as this is Javascript only.

Best regards, Michael

I primarily use Firefox

If I go to your gallery, the background image does display on first visit (didn't work on my gallery for some reason), but if I right click and "View Background Image" there's nothing, and if I try to Curl the URL with the &amp's in it, it's just an empty response (note no content-length):

$ curl -I 'https://www.tinywebgallery.com/demo/image.php?twg_album=03_Mexico+%282004%29&twg_type=png&twg_show=back.png'
HTTP/2 200
date: Tue, 25 May 2021 23:18:53 GMT
server: Apache/2.4.46 (Unix)
x-powered-by: PHP/8.0.6
expires: Thu, 19 Nov 1981 08:52:00 GMT
cache-control: no-store, no-cache, must-revalidate
pragma: no-cache
vary: User-Agent,Accept-Encoding
content-type: text/html; charset=UTF-8
set-cookie: PHPSESSID=0scd8o432c6u8b0rmo25vm1gvt; path=/
accept-ranges: none

$ curl 'https://www.tinywebgallery.com/demo/image.php?twg_album=03_Mexico+%282004%29&twg_type=png&twg_show=back.png'
$

On the other hand if I replace the & with & then I'm able to curl it:

$ curl -I 'https://www.tinywebgallery.com/demo/image.php?twg_album=03_Mexico+%282004%29&twg_type=png&twg_show=back.png'
HTTP/2 200
date: Tue, 25 May 2021 23:23:19 GMT
server: Apache/2.4.46 (Unix)
x-powered-by: PHP/8.0.6
expires: Thu, 19 Nov 1981 08:52:00 GMT
cache-control: no-store, no-cache, must-revalidate
pragma: no-cache
vary: User-Agent,Accept-Encoding
content-length: 69496
content-type: image/jpeg
set-cookie: PHPSESSID=be1r39k5s0psmfq6t2vsur3h0f; path=/

$ curl 'https://www.tinywebgallery.com/demo/image.php?twg_album=03_Mexico+%282004%29&twg_type=png&twg_show=back.png'
Warning: Binary output can mess up your terminal. Use "--output -" to tell
Warning: curl to output it to your terminal anyway, or consider "--output
Warning: <FILE>" to save to a file.
$            

Anyway if you've updated to replace the &amp's then all should be good, I'll try the updated version at some point but for now I have a rewrite rule in place that's working fine.

URL encoding in curl does of course not work. In the next small update this will be fixed. and like I wrote you you can easily also fix this...  only removing the amp in the line mentioned :).

Best regards,

Michael