Product view page scrolls up randomly on mobile device

[xiaolinwuu]

In the product view page when I scroll down a little bit, sometimes (very often) the page scrolls to the top.

Preconditions (*)

1. Magento 2.3.0 (in my case) but I think also in previous versions
2. Physical mobile device, Product view page

Steps to reproduce (*)

1. Go to any product view page
2. Scroll down slowly a little bit like 20-30px
3. If it can't reproduces retry again

Expected result (*)

1. The page should not scroll up automatically

Actual result (*)

1. The page scrolls up randomly

This is the effect:
https://www.youtube.com/watch?v=aKwLVwIMrpM

[magento-engcom-team]

Hi @xiaolinwuu. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

• Summary of the issue
• Information on your environment
• Steps to reproduce
• Expected and actual results

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

@magento-engcom-team give me 2.3-develop instance - upcoming 2.3.x release

For more details, please, review the Magento Contributor Assistant documentation.

@xiaolinwuu do you confirm that you was able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

[xiaolinwuu]

I found out the scroll up takes place only on mobile chrome application, I think the issue is caused by the chrome topbar that shows/hides when we manually scroll the page

[xiaolinwuu]

The issue was in the two elements of the fotorama widget:
.fotorama__active
.fotorama__img

They have top: 50% and position: absolute, so when chrome topbar shows/hides, the page suddenly jumps to the top.

I solved the problem extending the following css:

@media @mobile {
        .catalog-product-view {
            .fotorama__stage__frame.fotorama__active {
                position: static !important;
            }
            .fotorama__stage__frame .fotorama__img {
                position: static !important;
                transform: initial !important;
            }
       }
}

[magento-engcom-team]

Hi @shikhamis11. Thank you for working on this issue.
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[shikhamis11]

@magento-engcom-team give me 2.3-develop instance

[magento-engcom-team]

Hi @shikhamis11. Thank you for your request. I'm working on Magento 2.3-develop instance for you

[magento-engcom-team]

Hi @shikhamis11, here is your Magento instance.
Admin access: https://i-21717-2-3-develop.instances.magento-community.engineering/admin
Login: admin Password: 123123q
Instance will be terminated in up to 3 hours.

[magento-engcom-team]

@shikhamis11 Thank you for verifying the issue.

Unfortunately, not enough information was provided to acknowledge ticket. Please consider adding the following:

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Once all required information is added, please add label "Issue: Confirmed" again.
Thanks!