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  <xs:element id="tdup_AdjustmentsToAdditionalPaidInCapitalConsiderationDelayedShareIssuance" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalConsiderationDelayedShareIssuance" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tdup_DelayedShareIssuanceRelatedToAcquisitionMember" abstract="true" name="DelayedShareIssuanceRelatedToAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_StockIncentivePlan2010Member" abstract="true" name="StockIncentivePlan2010Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_SeriesDConvertiblePreferredStockIssued4202015Member" abstract="true" name="SeriesDConvertiblePreferredStockIssued4202015Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_StockholdersEquityConversionOfStockRatio" abstract="false" name="StockholdersEquityConversionOfStockRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tdup_DebtInstrumentMaximumBorrowingCapacity" abstract="false" name="DebtInstrumentMaximumBorrowingCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tdup_LesseeOperatingLeaseLeaseNotYetCommencedLiability" abstract="false" name="LesseeOperatingLeaseLeaseNotYetCommencedLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tdup_SellingStockholdersMember" abstract="true" name="SellingStockholdersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_SeriesE1ConvertiblePreferredStockIssued11252020Member" abstract="true" name="SeriesE1ConvertiblePreferredStockIssued11252020Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_ComputerEquipmentAndSoftwareMember" abstract="true" name="ComputerEquipmentAndSoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tdup_MarketingExpenseMember" abstract="true" name="MarketingExpenseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_TemporaryEquityConversionOfConvertibleSecuritiesShares" abstract="false" name="TemporaryEquityConversionOfConvertibleSecuritiesShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tdup_ShareBasedPaymentArrangementOptionVestingFourYearsFromCommencementMember" abstract="true" name="ShareBasedPaymentArrangementOptionVestingFourYearsFromCommencementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_GiftCardMember" abstract="true" name="GiftCardMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tdup_LoyaltyProgramMember" abstract="true" name="LoyaltyProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
