# Cannot modify the xblock info on Sumac **URL:** \ **Category:** Site Operators\ **Created:** [September 20, 2025, 11:25am UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179 "2025-09-20T11:25:58Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![vuthehuyht](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/vuthehuyht/32/7089_2.png) [@vuthehuyht](https://discuss.openedx.org/u/vuthehuyht)\ **Post date:** [September 20, 2025, 11:25am UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/1 "2025-09-20T11:25:58Z")
Hi everyone, I’m currently trying to customize the PDF XBlock so that it can work on Open edX Sumac. While working on this, I ran into a few issues: - After customizing and rebuilding the image locally, I added the PDF XBlock to _Advanced Settings_. - When I create a new module with the `pdf` block, I can’t open the modal editor to update its information. - I noticed that the interface is supposed to switch to the old Studio editor instead of the MFE Authoring, but this does not happen. - I also tested with pre-installed XBlocks like **SCORM** and **Google Document** , and the same issue occurs (the modal editor won’t open) Here is some images ![Screenshot from 2025-09-20 18-20-20](https://us1.discourse-cdn.com/flex020/uploads/openedx/original/2X/b/b233e321a31cf6588d0307301105de5b22cf2f7f.png) ![Screenshot from 2025-09-20 16-59-03](https://us1.discourse-cdn.com/flex020/uploads/openedx/original/2X/a/a865c0a0461e6b05930988f335bc50d197401658.png) ![Screenshot from 2025-09-20 18-14-41](https://us1.discourse-cdn.com/flex020/uploads/openedx/original/2X/8/8f9479e76958f8f1905b59657c6b24c3163310c6.png) Has anyone faced this issue before on Sumac? If so, how did you fix it? Any help would be much appreciated. ---
**Author:** ![sarina](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/sarina/32/2308_2.png) [@sarina](https://discuss.openedx.org/u/sarina)\ **Post date:** [September 22, 2025, 1:42pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/2 "2025-09-22T13:42:36Z")
@vuthehuyht could you kindly provide error traces in a code block, rather than a screenshot? ---
**Author:** ![braden](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/braden/32/46_2.png) [@braden](https://discuss.openedx.org/u/braden)\ **Post date:** [September 22, 2025, 5:15pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/3 "2025-09-22T17:15:13Z")
Try enabling the `legacy_studio.unit_editor` waffle flag, either for the course or for the whole Studio. I suspect there is an incompatibility between the PDF XBlock and the new Authoring MFE. If so, one of them will need to be fixed, but I’m not sure where the error lies. The NoUpstream exception in your third screenshot is unrelated and can be ignored. In fact, we shouldn’t be logging it as an exception since it’s kind of a “normal” status in most cases. CC @kmccormick ---
**Author:** ![vuthehuyht](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/vuthehuyht/32/7089_2.png) [@vuthehuyht](https://discuss.openedx.org/u/vuthehuyht)\ **Post date:** [September 28, 2025, 11:28am UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/4 "2025-09-28T11:28:26Z")
Thanks, that is the solution I need ---
**Author:** ![vuthehuyht](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/vuthehuyht/32/7089_2.png) [@vuthehuyht](https://discuss.openedx.org/u/vuthehuyht)\ **Post date:** [September 28, 2025, 11:32am UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/5 "2025-09-28T11:32:20Z")
@braden If I provide the source code of the PDF XBlock, can you point out where it is incompatible? ---
**Author:** ![kmccormick](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/kmccormick/32/8982_2.png) [@kmccormick](https://discuss.openedx.org/u/kmccormick)\ **Post date:** [September 29, 2025, 3:08pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/6 "2025-09-29T15:08:39Z")
Yes @vuthehuyht , please provide that, and we’ll do our best to find the incompatibility. ---
**Author:** ![vuthehuyht](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/vuthehuyht/32/7089_2.png) [@vuthehuyht](https://discuss.openedx.org/u/vuthehuyht)\ **Post date:** [September 29, 2025, 4:12pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/7 "2025-09-29T16:12:44Z")
@kmccormick here is the version I have customized > **[GitHub - vuthehuyht/xblock-pdf](https://github.com/vuthehuyht/xblock-pdf)** > > Contribute to vuthehuyht/xblock-pdf development by creating an account on GitHub. ---
**Author:** ![vuthehuyht](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/vuthehuyht/32/7089_2.png) [@vuthehuyht](https://discuss.openedx.org/u/vuthehuyht)\ **Post date:** [October 1, 2025, 5:07pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/8 "2025-10-01T17:07:43Z")
> [@braden](#): > > legacy\_studio.unit\_editor I have tried to enable the `legacy_studio.unit_editor` flag but the editor still use the MFE ![image](https://us1.discourse-cdn.com/flex020/uploads/openedx/optimized/2X/6/6f355488cf16257f17a808aa5f6dedef26012e32_2_690x30.png) ---
**Author:** ![braden](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/braden/32/46_2.png) [@braden](https://discuss.openedx.org/u/braden)\ **Post date:** [November 10, 2025, 3:47pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/9 "2025-11-10T15:47:00Z")
> [@vuthehuyht](#): > > I have tried to enable the `legacy_studio.unit_editor` flag but the editor still use the MFE It looks like you tried a flag called `studio.legacy_studio.unit_editor` but I believe it should be just `legacy_studio.unit_editor`. ---
**Author:** ![kmccormick](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/kmccormick/32/8982_2.png) [@kmccormick](https://discuss.openedx.org/u/kmccormick)\ **Post date:** [November 12, 2025, 3:40pm UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/10 "2025-11-12T15:40:23Z")
Hey @vuthehuyht , I recently tested the new unit editor with both your PDFXBlock and [RaccoonGang’s PdfXBlock](https://github.com/raccoongang/xblock-pdf) and did not encounter any issues. I was testing with Ulmo, so **you are probably encountering a bug that existed in the Sumac release but was fixed since then**. Here’s the new unit editor in Ulmo with the PDF block: ![image](https://us1.discourse-cdn.com/flex020/uploads/openedx/original/2X/c/cbdc40b7d410cc8694a1df65166630ff0030e337.png) Here’s what I recommend: - For Sumac, ensure that the `contentstore.new_studio_mfe.use_new_unit_page` waffle flag is set to No (False). This will ensure that you are using the legacy unit editor, which works with the PDF block. - When you upgrade to Teak, ensure that `legacy_studio.unit_editor` is set to Yes (True). This will ensure that you continue using the legacy unit editor. - When you upgrade to Ulmo, try setting `legacy_studio.unit_editor` back to No (False). This will switch you to the new unit editor. **If you still see the issue in Ulmo, then let us know.** ---
**Author:** ![vuthehuyht](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.openedx.org/vuthehuyht/32/7089_2.png) [@vuthehuyht](https://discuss.openedx.org/u/vuthehuyht)\ **Post date:** [November 21, 2025, 3:30am UTC](https://discuss.openedx.org/t/cannot-modify-the-xblock-info-on-sumac/17179/11 "2025-11-21T03:30:54Z")
Thanks very much