[GH-ISSUE #1787] 13 custom fields renders 4/10 times on ESP8266 #1504

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opened 2026-02-28 01:30:20 +03:00 by kerem · 4 comments

kerem commented

2026-02-28 01:30:20 +03:00

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Originally created by @F1p on GitHub (Dec 24, 2024).
Original GitHub issue: https://github.com/tzapu/WiFiManager/issues/1787

I have a reasonable sized project, running 13 custom fields and have an issue on the ESP8266 where 4/10 times the custom fields render blank on refresh (as per screenshots) but issue doesn't seem to impact the ESP32. Any idea's why this might happen?

Running the latest master branch,

ESP8266 running
Core version
3.1.2
Boot version
31
CPU frequency
160MHz
Memory - Free heap
12912 bytes available
Memory - Sketch size
Used / Total bytes
489296 / 3143504

Originally created by @F1p on GitHub (Dec 24, 2024). Original GitHub issue: https://github.com/tzapu/WiFiManager/issues/1787 I have a reasonable sized project, running 13 custom fields and have an issue on the ESP8266 where 4/10 times the custom fields render blank on refresh (as per screenshots) but issue doesn't seem to impact the ESP32. Any idea's why this might happen? ![Screenshot 2024-12-19 133629](https://github.com/user-attachments/assets/a5f8f259-2961-4f43-b57d-15cac21a7fca) ![Screenshot 2024-12-19 134342](https://github.com/user-attachments/assets/96f7d2d9-f508-40b7-935a-026d678a1d6f) Running the latest master branch, ESP8266 running Core version 3.1.2 Boot version 31 CPU frequency 160MHz Memory - Free heap 12912 bytes available Memory - Sketch size Used / Total bytes 489296 / 3143504

kerem commented

2026-02-28 01:30:20 +03:00

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@F1p commented on GitHub (Dec 29, 2024):

Might be an issue improved by adjusting MMU to 16KB Cache + 48K IRAM instead of balanced (32/32K)

@F1p commented on GitHub (Dec 29, 2024): Might be an issue improved by adjusting MMU to 16KB Cache + 48K IRAM instead of balanced (32/32K)

kerem commented

2026-02-28 01:30:20 +03:00

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@tablatronix commented on GitHub (Dec 30, 2024):

Its probably memory, the html is output as a string on the stack, If you are using alot of params this can be optimized by using chunked outputting and allocated buffers, I think there is an issue here to start looking into it..

#1319
#518

@tablatronix commented on GitHub (Dec 30, 2024): Its probably memory, the html is output as a string on the stack, If you are using alot of params this can be optimized by using chunked outputting and allocated buffers, I think there is an issue here to start looking into it.. #1319 #518

kerem commented

2026-02-28 01:30:20 +03:00

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@F1p commented on GitHub (Dec 30, 2024):

Its probably memory, the html is output as a string on the stack, If you are using alot of params this can be optimized by using chunked outputting and allocated buffers, I think there is an issue here to start looking into it..

#1319 #518

Thanks, will try chunked response for now

@F1p commented on GitHub (Dec 30, 2024): > Its probably memory, the html is output as a string on the stack, If you are using alot of params this can be optimized by using chunked outputting and allocated buffers, I think there is an issue here to start looking into it.. > > #1319 #518 Thanks, will try chunked response for now

kerem commented

2026-02-28 01:30:20 +03:00

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@timr49 commented on GitHub (Jun 29, 2025):

Its probably memory, the html is output as a string on the stack, If you are using alot of params this can be optimized by using chunked outputting and allocated buffers, I think there is an issue here to start looking into it..
#1319 #518

Thanks, will try chunked response for now

Hi F1p, not sure how you went with the previous suggestion to try chunked responses. If helps, I developed a chunking enhancement for WiFiManager, which you can get from branch Chunking in the repo https://github.com/timr49/WiFiManager
It is described in https://github.com/timr49/WiFiManager/blob/Chunking/PAGE.md

@timr49 commented on GitHub (Jun 29, 2025): > > Its probably memory, the html is output as a string on the stack, If you are using alot of params this can be optimized by using chunked outputting and allocated buffers, I think there is an issue here to start looking into it.. > > [#1319](https://github.com/tzapu/WiFiManager/pull/1319) [#518](https://github.com/tzapu/WiFiManager/issues/518) > > Thanks, will try chunked response for now Hi F1p, not sure how you went with the previous suggestion to try chunked responses. If helps, I developed a chunking enhancement for WiFiManager, which you can get from branch Chunking in the repo https://github.com/timr49/WiFiManager It is described in https://github.com/timr49/WiFiManager/blob/Chunking/PAGE.md