Hello. I sent a notification about your question to the company employees, expect an answer from them here in the comments.

Hello Malcolm

Please try to restart the program and perform a new upload as reported by Sinisa first.

If the issue is still present, please share your website's URL here so that I might check the page personally for you. I will try to understand what might be causing the issue you're encountering

Keep me posted on this here

Thank you

Stefano

Thank you Sinisa & Stefano.

Unfortunately the problem remains after restarting WX5, Control-Preview and uploading all files. I did not wipe the live site prior to uploading again, but as noted previously the symptoms are identical on a local preview so that is unlikely to be the cause.

See:
http://www.colourfasteditions.co.uk/tashi-mannox.html
http://www.colourfasteditions.co.uk/peter-crosland.html
http://www.colourfasteditions.co.uk/eugene-fisk.html
etc.

The issue is most noticeable on those pages (above) where the gallery contains larger numbers of images. On first opening the page, the grid builds image by image before reverting to the correct single line thumbnail display once it has loaded all the images.

Reopening the page is quicker on subsequent occasions as the images are presumably then already cached, but the grid still flashes up briefly before settling down into the correct display. As confirmed by Sinisa, this is 'new' behaviour but I can't say for certain with which update it began.

Thank you for your assistance.

Malcolm

Malcolm, I opened each of your links but only identified your issue (briefly) on the first link. Could this simply be associated with a slow internet connection?

Many of my pages load in a "default" format but revert to the correct format once all the page code has loaded, normally this is almost un-noticeable, but on poor internet connections (not necessarily at my end, frequently because of network latency or congestion) this is quite noticeable. One primary culprit was  Nortons AV causing significant delays as it checked each page load, I now simply use defender (win10)

Do you experience the problem with your galleries on other PCs at other locations?

PS I just found it is extremely easy to see the issue you are referring to if you open the appropriate pages and click ctrl+F5

Malcolm, on my iPad, the site loads instantly and the "grid of images" only appears for about a tenth of a second (barely noticable).

My Internet connection speed is high -- 330 Mbps for download -- so everything works very well on your site.

No, my internet connection is ~ 330Mbps FTTP and the identical issue also occurs locally using the WX5 preview, albeit with less of a delay but still visible, so it is not a function of connection speed or latency, nor an issue on the hosting server.

Esahc, I had already checked the above links on the live site after uploading the site again and prior to my last post, so it is possible they may have been at least partially cached when you first checked the pages; the issue is most noticeable on the initial page opening but also recurs with less of a delay on subsequent visits. As you note in your subsequent postscript, Ctrl-F5 shows the behaviour more clearly, analogous to an initial page visit. 

I am also using Win 10 Defender. The issue is identical on a second PC.

The point is that it is (a) distracting to the viewer, and (b) that it never used to happen and has only occurred recently, so something has definitely changed in recent versions.

I do still have historic .iwzips dating back to v2019.1 and 2019.3 with those pages unchanged, and possibly earlier, so I can if necessary download and reinstall earlier version(s) of the software for further testing if no solution is otherwise forthcoming, but it will be a bit of a pain to do so.

Malcolm, I created an empty project in v16, added a gallery (horizontal thumbnails single line, visible 5) just like yours and threw about 40 images into it.

On load the page ONLY shows the single row as designed and as you would prefer.

However

When I did the same thing in v17 and v2019.1 and later I got the same issue you are concerned about (a momentary display of all images in rows down the page and then it reverts to a single row as required).

It appears that this behaviour crept in with the release of v17 so I suspect the response from Incomedia will be that this is "expected behaviour". It will be interesting to see if google feels your site now runs foul of CLS (https://web.dev/cls/) as mentioned in this post https://helpcenter.websitex5.com/en/post/228635

Esahc, thank you for taking the time and the trouble to look deeper into this - much appreciated.

My own feeling is that the change in behaviour crept in more recently than that, as I had made updates & new uploads to the site in both v17 and v19, and I don't recall any such behaviour at that time. I don't have a record of the individual WX5 version release dates, but fortunately I still have historic .iwzips dating back to Jan, March, April and June 2019 at least, and possibly others elsewhere, as well as from earlier this year, which I believe together span the v2017, v2019 and v2020 software releases so that I can if necessary reload those earlier versions of WX5 and check definitively.

I'm inclined at the moment to see what Incomedia come up with first but will revert and test further if they can't confirm or offer a solution. It may or may not be "expected behaviour", but it's certainly undesirable and it looks unprofessional.

Some 6 months or so ago Google did complain about the font size on the site (which I disagreed with, for what it's worth - it was perfectly readable as it was) and I have since corrected that, but they haven't mentioned CLS or anything else since. (Thanks for the pointer to CLS, by the way - I hadn't come across that before.) I can't now recall the appropriate link, but I believe it is possible to force a manual check of the site by Google, so I'll have a dig and see what they say.

Thank you, Stefano. If I find anything meanwhile that sheds any further light, I'll update here.

(Google | It > En) ... if you are interested, with an EXTRA code, you could try to delay the presentation of the images at the end of the page load, temporarily showing a loader as for example in this STAMP ...
... so if you are interested, let me know ...

ciao

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