Cause of this problem

[bigboy3879]

hello im new to community i have a issue i recently reinstalled magento 2.3 and viewed both default themes blank and luma just today switched back to luma from blank and have this error on homepage only this is my online marketplace i am slowly working on here is home page https://www.triple8dealz.com/ i am changing domain name soon i got this one a whim just to set up hosting account please visit homepage them click on a demo product and see luma theme then go back to homepage there you will see this where no header no footer just products and i have changed everything back to luma tryed flushing static files cache reindexing i dont understand what is happening

[PankajS_Magento]

Hi @bigboy3879 

I have a solution might work for you.

Copy default.xml file from the Magento vendor directory:

vendor/magento/module-theme/view/frontend/layout/default.xml

To

app\design\frontend\themepackage\themename\Magento_Theme\layout\default.xml

and then run below commands:

sudo rm -Rf pub/static/frontend/* pub/static/_requirejs/*
sudo php bin/magento setup:static-content:deploy -f
sudo php bin/magento cache:clean
sudo php bin/magento cache:flush
sudo chmod -R 777 var/ pub/

Thanks

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[bigboy3879]

Hello the app/design/frontend/magento 2 directory is empty if i do this will it affect the default themes im currently using 

[PankajS_Magento · Accepted solution]

@bigboy3879 

It means that you are using default Magento 2 theme. But I would recommend you to create a custom theme. Here is the link will help you to create a custom theme.

OR

For fix above error. Run below commands:

sudo rm -Rf pub/static/frontend/* var/pre_processed/* pub/static/_requirejs/*
sudo rm -Rf var/generation/* var/di/* var/cache/*
sudo php bin/magento setup:upgrade
sudo php bin/magento setup:di:compile
sudo php bin/magento setup:static-content:deploy -f
sudo php bin/magento cache:clean
sudo php bin/magento cache:flush
sudo chmod -R 777 var/ pub/ generated/

I hope it will work for you.

Thanks

--
If my answer is useful, please Accept as Solution & give Kudos

[bigboy3879]

Thank you much for your assistance i will follow this to create a custom theme