Hi @luukschakenraad. Thank you for your contribution
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I might be wrong about this, but it could be that this is trying to fix the same issue as #18443 is trying to fix (but that one is for a lot more options of fotorama)

I might be wrong about this, but it could be that this is trying to fix the same issue as #18443 is trying to fix (but that one is for a lot more options of fotorama)

That one seems to be unrelated to this issue. This one has nothing to do with any settings. It's just a bug in Fotorama which causes wrong behaviour of the previous and next buttons.

Well, actually they are related :)

I just played around a bit with this, if I take a clean Magento 2.2.6 installation, then apply the changes from:

• 0255ce3
• https://github.com/magento/magento2/pull/18443/files

And then re-test, all the issues you mention in #18585 are fixed.

Here's why, these are the configuration values outputted in the html for the fotorama library:

Vanilla 2.2.6:

{
    "fullscreen": {
        "arrows": 1,
        "loop": 1,
        "nav": "thumbs",
        "navdir": "horizontal",
        "navtype": "slides",
        "transition": "slide",
        "transitionduration": 500
    },
    "options": {
        "allowfullscreen": 1,
        "arrows": 1,
        "height": 560,
        "keyboard": 1,
        "loop": 1,
        "nav": "thumbs",
        "navarrows": 1,
        "navdir": "horizontal",
        "navtype": "slides",
        "thumbheight": 110,
        "thumbwidth": "88",
        "transition": "slide",
        "transitionduration": 500,
        "width": "700"
    }
}

After applying two fixes mentioned above:

{
    "fullscreen": {
        "arrows": true,
        "loop": true,
        "nav": "thumbs",
        "navarrows": false,
        "navdir": "horizontal",
        "navtype": "slides",
        "showCaption": false,
        "transition": "slide",
        "transitionduration": 500
    },
    "options": {
        "allowfullscreen": true,
        "arrows": true,
        "height": 560,
        "keyboard": true,
        "loop": true,
        "nav": "thumbs",
        "navarrows": true,
        "navdir": "horizontal",
        "navtype": "slides",
        "showCaption": false,
        "thumbheight": 110,
        "thumbwidth": 88,
        "transition": "slide",
        "transitionduration": 500,
        "width": 700
    }
}

You'll notice that in the fixed code, a lot of values 1 changed to the more correct value true.
For some reason, if you pass on 1 to the toggle function from jQuery, it will switch on and off and on and off, don't ask me why, my javascript knowledge isn't what it used to be. You can find a demo in https://jsfiddle.net/ot0adbhv/ (click the button a couple of times to see its behavior)

I'll leave this open for now, so a community maintainer can decide what to do with it, but in my opinion there is already a proper fix for the issue in #18443.

You are absolutely right @hostep, very well spotted. It's my double not operator that transforms the number into a boolean and in #18443 the setting is directly set as boolean.

In my opinion, both fixes can be applied as:

• they won't conflict
• The !! is also in Fotorama's source-code
• gallery.phtml may be overwritten by a theme or module in which case a user can not get the advantages of fix [Backport][2.2] Reworked gallery.phtml to move generation of gallery json strings to own block functions #18443.

• The !! is also in Fotorama's source-code

Ah yes, you are correct, I wasn't aware of this!

Did it little more research, so just for some extra context:

• It was added in Fotorama in: artpolikarpov/fotorama@097e27e#diff-a8ba3933459ba275512d8b6c005bea21L269
• It was removed again in Magento's fork in: 3840124#diff-86f4d0a1cbadb052fcfe8b0f21cff058L2413

Not sure why it got removed in Magento though ...

But if we have to get it back in Magento, I suggest you also edit the fotorama.min.js file, I believe this file should be edited manually, I don't think there is some automatic process to generate the minified version.

I now changed the minified version as well. I did the same for pull request #18590

Hi @sidolov, thank you for the review.
ENGCOM-3200 has been created to process this Pull Request

Hi @luukschakenraad. Thank you for your contribution.
We will aim to release these changes as part of 2.2.8.
Please check the release notes for final confirmation.

Please, consider to port this solution to 2.3 release line.
You may use Porting tool to port commits automatically.