Quote line items bugged 10.3?

Doing a bit more digging, do you have any customization in custom/modules/Quotes/clients/base/views/record/record.js ? 

Yes. But I don't think they are related. 

({
    extendsFrom: 'RecordView',

    /**
     * @inheritdoc
     */
    initialize: function (options) {
        this._super('initialize', [options]);
        this.context.on('button:send_pdf:click', this.onSendPdf, this);
        this.context.on('button:print_pdf:click', this.onPrintPdf, this);
        this.model.on('change:billing_account_name',this.onBillingAccountChange,this); //needs to be refactored
        this.model.on('change:billing_account_id',this.onBillingAccountChange,this); 
    },

    onBillingAccountChange: function (data){
        if(!data.inSync) {
            let billing_account_name = this.model.get('billing_account_name');
            let billing_account_id = this.model.get('billing_account_id');
            this.model.set('shipping_account_name', billing_account_name);
            this.model.set('shipping_account_id', billing_account_id);
        }
    },

    onSendPdf: function(){
        var urlParams = $.param({
            'action': 'tcpdf_offer',
            'module': this.module,
            'record': this.model.id,
            'mode' : 'FMail'
        });

        var url = '?' + urlParams;

        app.alert.show('generating_pdf', {
            level: 'process',
            title: app.lang.get('LBL_GENERATING_PDF')
        });

        app.bwc.login(null,_.bind(function(){
            this._triggerDownload(url);
        },this));

    },
    onPrintPdf: function(){
      this.model.get('id');
      var urlParams = $.param({
          'action': 'tcpdf_offer',
          'module': this.module,
          'record': this.model.id,
      });
      var url = '?' + urlParams;

        app.alert.show('generating_pdf', {
            level: 'process',
            title: app.lang.get('LBL_GENERATING_PDF')
        });

      app.bwc.login(null,_.bind(function(){
          this._triggerDownload(url);
      },this));
    },
    _triggerDownload: function(url) {
        app.api.fileDownload(url, {
            success: function() {
                app.alert.dismiss('generating_pdf');
            },
            error: function(data) {
                // refresh token if it has expired
                app.alert.dismiss('generating_pdf');
                app.error.handleHttpError(data, {});
            }
        }, {iframe: this.$el});
    },
})

Hi Jeroen Somhorst

I noticed that several customizations you had placed at record.js could be moved to custom field templates instead, in order to follow best practices.

Whenever you want to listen to a field and take some action then it would be better to create a custom field template for that purpose, this way you, probably, will not have a custom record.js anymore.

This way your solution become even more flexible and safe from custom customization eventually applied by installed packages.

Regards

Hi Jeroen Somhorst

I noticed that several customizations you had placed at record.js could be moved to custom field templates instead, in order to follow best practices.

Whenever you want to listen to a field and take some action then it would be better to create a custom field template for that purpose, this way you, probably, will not have a custom record.js anymore.

This way your solution become even more flexible and safe from custom customization eventually applied by installed packages.

Regards