Ideally this should use session storage as this information is only really needed inside a session.

It's unfortunate that the Web Platform calls this "session storage". A more accurate name (based on the documentation) would be "tab storage".

If the expanded section feature only needs to store information on a single page view (with perhaps the the extra persistence of backward/forward and "re-open closed tab" navigations that re-create that same page view in the same tab), then sessionStorage is great. If not, then you probably don't want that.

In a nut shell: sessionStorage is not like a session cookie. There is no equivalent to session cookies in HTML5 Storage.

This causes localStorage to grow.

Note that the quota for sessionStorage generally isn't different or larger. Why does it grow? What's the ideal max size? Can it be limited?

the expanded section feature only needs to store information on a single page view (with perhaps the the extra persistence of backward/forward and "re-open closed tab" navigations that re-create that same page view in the same tab), then sessionStorage is great. If not, then you probably don't wan that.

the purpose of the feature is solely to restore back button behavior - so if a user clicks a link in a section and returns to the page they find themselves in the same position.

Note that the quota for sessionStorage generally isn't different or larger. Why does it grow? What's the ideal max size? Can it be limited?

We could limit it yes, but given the purpose is only for sessions, I'm not sure if there are any advantages to let it grow. Right now if I visit an article and then visit it again 3 months later the sections will remain open. That doesn't seem useful and is also inaccurate given those sections may have rearranged.

Awesome. That's quite literally a perfect fit for sessionStorage.

Hi @Jdlrobson ,
Can you tell me which extension I have to download to solve this issue?

@Yash4357 you'll need to install MobileFrontend (https://gerrit.wikimedia.org/r/admin/repos/mediawiki/extensions/MobileFrontend)
as well as the Minerva skin https://mediawiki.org/wiki/Skin:MinervaNeue

In T253137#6728979, @Yash4357 wrote:

Hi @Jdlrobson ,
Can you tell me which extension I have to download to solve this issue?

It's Extension:MobileFrontend, and source is here

Do I have to download the geodata , pageImages, Visual Editor extensions.

No, why do you think so?

Because it is mention in link : https://www.mediawiki.org/wiki/Extension:MobileFrontend
that Get the most out of MobileFrontend by adding these optional compatible extensions.

I have replace the mw.storage with mw.storage.session in the toggler.js,
but then also it is showing the expandedSection in the localstorage, and nothing in the sessionStorage.

In T253137#6729575, @Yash4357 wrote:

I have replace the mw.storage with mw.storage.session in the toggler.js,
but then also it is showing the expandedSection in the localstorage, and nothing in the sessionStorage.

I'm not 100% sure what you mean here. If it's still saving to localStorage then something is not quite right with your patch. Note, ideally this patch will remove any existing items in localStorage from the previous code.

Hi @Jdlrobson,
When I am doing git commit it is showing me this type of interface:

That is the precommit. It is telling you that there are tests that are failing because of your changes. You will need to run git commit --no-verify to override.

Change 655102 had a related patch set uploaded (by Yash9265; owner: Yash9265):
[mediawiki/extensions/MobileFrontend@master] MobileFrontend should use sessionStorage for expandedSections

https://gerrit.wikimedia.org/r/655102

Change 655102 merged by jenkins-bot:
[mediawiki/extensions/MobileFrontend@master] MobileFrontend should use sessionStorage for expandedSections

https://gerrit.wikimedia.org/r/655102

Test Result - Beta

Status: ✅ PASS
Environment: beta
OS: iOS 14.2.1
Browser: Safari
Device: iPhone 12 Max Pro
Emulated Device: NA

Test Artifact(s):

QA Steps

Visit beta cluster page on a mobile device with headings e.g. https://en.m.wikipedia.beta.wmflabs.org/wiki/Albert_Einstein sections should be collapsible by default.
Expand 3 sections
Click a link in one of the 3 sections
Hit the back button to go back to the Albert Einstein page.
AC1: Expected: when going back the 3 sections you opened in step 2 should still be open.