Hi, thank you for reaching out and for taking the time to report this issue with such detailed information.

This scenario will be investigated further to see what might be causing the excessive memory usage and whether improvements can be made.

In the meantime, you may consider temporarily downgrading to PhotoShow 4.89.2 (https://addons.mozilla.org/en-US/firefox/addon/photoshow/versions/). It has more limited support for subframes and does not include some of the latest features, but it should also have lower memory usage.

Further updates on the investigation will be posted here. Thanks again for the report, and cheers!

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Edited - 30 July 2026:

Hi, just a quick update. Some investigation has been done into the reported memory usage issue, however, further information is needed to reproduce it. If possible, could you provide a bit more details? Specifically,

- When you mentioned "Firefox sleeping tabs", were you referring to Firefox's built-in "Unload Tab" feature, or a third-party extension or application?

- Roughly how many tabs did you have open in total, including inactive or sleeping ones?

- When you said "activate this add-on", what exactly did that mean? For example, was it enabling PhotoShow from Firefox's Add-ons Manager, or performing some other action?

- What's your PhotoShow version when you had this issue?

If it's more convenient, feel free to share these details via GitHub, the PhotoShow Discord community, or email, where they can be followed up more easily if additional information is needed.

Thanks again for taking the time to report the issue and help improve PhotoShow!